Authenticity determination system, authenticity determination device, program, and authenticity determination method

Abstract

To obtain an authenticity determination system capable of simply determining the authenticity of an electronic document.SOLUTION: An authentication determination system includes a first server for creating and storing an electronic document, a second server for managing address information, and an operation terminal to be operated by a user. The operation terminal transmits an execution request for authentication determination processing to an electronic document of a determination object to the second server. In the authentication determination processing, the second server transmits a reply request for address information included in the electronic document of the determination object displayed on the screen of the operation terminal to the operation terminal. The operation terminal acquires and transmits the address information included in the electronic document of the determination object displayed on the screen to the second server. The second server determines the authenticity of the electronic document of the determination object as to whether the address information received from the operation terminal is normal.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an authenticity determining system, an authenticity determining device, a program, and an authenticity determining method for an electronic document. [Background technology]

[0002] Patent Document 1 discloses a content certification system according to the background art. According to this system, a document such as a certificate displays an image of a two-dimensional code in addition to text information. The image stores the text information, signature information (encrypted using a private key) including a hash value of the text information, and an email address of a verification server. When a verifier takes an image using a camera of a mobile phone, the mobile phone sends the image information to the email address of the verification server by email. The verification server reads out the text information stored in the image and calculates a hash value of the text information. The verification server compares the calculated hash value with the hash value included in the signature information (decrypted using a public key) read from the image, and determines the authenticity of the document depending on whether the two match. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-341253 A Summary of the Invention [Problem to be solved by the invention]

[0004] The system disclosed in Patent Document 1 requires management of private keys and public keys, and calculation of hash values ​​in the verification server, making the processing complicated.

[0005] The present invention has been made in consideration of the above circumstances, and has an object to provide an authenticity determination system, an authenticity determination device, a program, and an authenticity determination method that are capable of easily determining the authenticity of an electronic document. [Means for solving the problem]

[0006] An authenticity determination system according to a first aspect of the present invention comprises a first server that creates and stores an electronic document, a second server that is managed by the issuer of the electronic document and manages address information indicating the address at which the electronic document is stored, and an operation terminal operated by a user who uses the electronic document, wherein the electronic document includes the address information related to the electronic document, and the operation terminal sends a request to the second server to execute an authenticity determination process for the electronic document to be determined, and in the authenticity determination process, the second server sends to the operation terminal a return request for the address information included in the electronic document to be determined that is displayed on the screen of the operation terminal, the operation terminal obtains the address information included in the electronic document to be determined that is displayed on the screen and sends it to the second server, and the second server determines the authenticity of the electronic document to be determined based on whether the address information received from the operation terminal is legitimate or not.

[0007] According to the first aspect, an electronic document includes address information related to the electronic document, and an operation terminal acquires the address information included in the electronic document to be judged that is displayed on a screen and transmits it to a second server, and the second server judges the authenticity of the electronic document to be judged based on whether the address information received from the operation terminal is legitimate. Therefore, it is possible to judge the authenticity of an electronic document by a simple process of judging whether the address information included in the electronic document to be judged is legitimate.

[0008] In the authenticity determination system according to the second aspect of the present invention, in the first aspect, the electronic document includes the address information related to the electronic document as an image, and the operation terminal obtains the address information by using a camera to capture the image included in the electronic document to be determined that is displayed on the screen.

[0009] According to the second aspect, the operation terminal acquires address information by capturing an image of the electronic document to be judged that is displayed on the screen with a camera. Therefore, it is possible to acquire address information included in the electronic document to be judged by the simple process of capturing an image with a camera.

[0010] In the second aspect of the authenticity determination system according to the third aspect of the present invention, if the address information received from the operation terminal is genuine, the second server transmits a genuine electronic document corresponding to the address information to the operation terminal, and displays the genuine electronic document on the screen of the operation terminal.

[0011] According to the third aspect, if the address information received from the operation terminal is legitimate, the second server transmits the legitimate electronic document corresponding to the address information to the operation terminal and displays the legitimate electronic document on the screen of the operation terminal, thereby enabling the operator of the operation terminal to easily confirm that the electronic document to be judged has not been tampered with by visually comparing the electronic document to be judged displayed on the screen with the legitimate electronic document.

[0012] An authenticity determination device according to a fourth aspect of the present invention is an authenticity determination device that is managed by the issuer of an electronic document, manages address information indicating the address at which the electronic document is stored, and determines the authenticity of the electronic document, and is equipped with a receiving unit, a transmitting unit, and a determination unit, wherein the electronic document includes the address information related to the electronic document, and the receiving unit receives a request to execute an authenticity determination process for the electronic document to be determined from an operation terminal operated by a user who uses the electronic document to be determined, and in the authenticity determination process, the transmitting unit sends to the operation terminal a return request for the address information contained in the electronic document to be determined that is displayed on the screen of the operation terminal, and the receiving unit receives from the operation terminal the address information contained in the electronic document to be determined that is displayed on the screen, and the determination unit determines the authenticity of the electronic document to be determined based on whether the address information received from the operation terminal is legitimate or not.

[0013] According to a fourth aspect, an electronic document includes address information related to the electronic document, the receiving unit receives from the operating terminal the address information included in the electronic document to be judged that is displayed on the screen of the operating terminal, and the judging unit judges the authenticity of the electronic document to be judged based on whether the address information received from the operating terminal is legitimate. Therefore, it is possible to judge the authenticity of an electronic document by a simple process of judging whether the address information included in the electronic document to be judged is legitimate.

[0014] A program according to a fifth aspect of the present invention is a program that causes an information processing device managed by an issuer of an electronic document, managing address information indicating the address at which the electronic document is stored, and equipped with an authenticity determination device that determines the authenticity of the electronic document, to function as a receiving means, a transmitting means, and a determining means, wherein the electronic document includes the address information related to the electronic document, the receiving means receives a request to execute an authenticity determination process for the electronic document to be determined from an operation terminal operated by a user who uses the electronic document to be determined, and in the authenticity determination process, the transmitting means transmits a return request for the address information included in the electronic document to be determined that is displayed on the screen of the operation terminal to the operation terminal, the receiving means receives the address information included in the electronic document to be determined that is displayed on the screen from the operation terminal, and the determining means determines the authenticity of the electronic document to be determined depending on whether the address information received from the operation terminal is legitimate or not.

[0015] According to the fifth aspect, the electronic document includes address information related to the electronic document, the receiving means receives from the operation terminal the address information included in the electronic document to be judged that is displayed on the screen of the operation terminal, and the judging means judges the authenticity of the electronic document to be judged based on whether the address information received from the operation terminal is legitimate. Therefore, it is possible to judge the authenticity of the electronic document by the simple process of judging whether the address information included in the electronic document to be judged is legitimate.

[0016] An authenticity determination method according to a sixth aspect of the present invention is an authenticity determination method executed by an authenticity determination device that is managed by the issuer of an electronic document, manages address information indicating the address at which the electronic document is stored, and determines the authenticity of the electronic document, wherein the electronic document includes the address information related to the electronic document, a request to execute an authenticity determination process for the electronic document to be determined is received from an operation terminal operated by a user who uses the electronic document to be determined, and in the authenticity determination process, a return request for the address information contained in the electronic document to be determined that is displayed on the screen of the operation terminal is sent to the operation terminal, the address information contained in the electronic document to be determined that is displayed on the screen is received from the operation terminal, and the authenticity of the electronic document to be determined is determined based on whether the address information received from the operation terminal is legitimate.

[0017] According to a sixth aspect, an electronic document includes address information related to the electronic document, and the authenticity determination device receives, from the operation terminal, the address information included in the electronic document to be determined and displayed on the screen of the operation terminal, and determines the authenticity of the electronic document to be determined based on whether the address information received from the operation terminal is legitimate. Therefore, it is possible to determine the authenticity of an electronic document by a simple process of determining whether the address information included in the electronic document to be determined is legitimate. Effect of the Invention

[0018] According to the present invention, it is possible to easily determine the authenticity of an electronic document. [Brief description of the drawings]

[0019] [Figure 1] 1 is a diagram showing a simplified overall configuration of an authenticity determination system according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a diagram showing a simplified configuration of a first server. [Diagram 3] FIG. 2 is a diagram showing a simplified configuration of a second server. [Figure 4] FIG. 2 is a diagram showing a simplified configuration of an operation terminal. [Diagram 5] FIG. 2 is a diagram showing a simplified configuration of a user terminal. [Figure 6] FIG. 2 is a simplified diagram illustrating an example of an electronic document. [Figure 7] 10 is a sequence diagram showing transmission and reception of information among a first server, a second server, an operation terminal, and a user terminal. FIG. [Figure 8] 13 is a flowchart showing a process executed by a processing unit of a second server in an authenticity determination process for determining an electronic document. [Figure 9] FIG. 2 is a simplified diagram showing a display example of a screen of a display unit. [Figure 10] 13 is a simplified diagram showing an example of a display on the screen of the display unit when the operation terminal receives information including a legitimate determination result. FIG. [Figure 11] 13 is a simplified diagram showing an example of a display on the screen of the display unit when the operating terminal receives information including a fraud determination result. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In addition, elements with the same reference numerals in different drawings indicate the same or corresponding elements.

[0021] 1 is a simplified diagram showing the overall configuration of an authenticity determination system 1 according to an embodiment of the present invention. The authenticity determination system 1 includes a first server 2, a second server 3, an operation terminal 4, and a user terminal 5. The first server 2, the second server 3, the operation terminal 4, and the user terminal 5 are all connected to a communication network 6. The communication network 6 is any dedicated line network or public line network such as an IP (Internet Protocol) network.

[0022] The second server 3 is managed by an issuer 12 of the electronic document 100. In this embodiment, the issuer 12 is an entity that implements various qualification tests, certification tests, or accreditation tests, and the electronic document 100 is a passing certificate, a transcript, or an official certification for those tests. However, the electronic document 100 is not limited to this example, and may be any document on an electronic medium.

[0023] The first server 2 is managed by a management company 11 that creates and stores the electronic document 100. The first server 2 creates the electronic document 100 based on test information received from the issuer company 12. The first server 2 stores the created electronic document 100 in a state where security is ensured. The electronic document 100 is stored in an HDD, SSD, semiconductor memory, or the like in the first server 2. However, the electronic document 100 may be stored in a blockchain network or the like outside the first server 2. The first server 2 stores the electronic document 100 in a predetermined address in the storage location, and transmits address information 101 such as a URL indicating the address to the second server 3. The second server 3 manages the received address information 101 by storing it in a state where security is ensured. The address information 101 is stored in an HDD, SSD, semiconductor memory, or the like in the second server 3.

[0024] The user terminal 5 is a PC, tablet, smartphone, or the like, owned by an individual user 14 who has taken the above-mentioned various examinations. The user 14 is notified of address information 101 related to an electronic document 100 such as a passing certificate by the management business operator 11 or the issuing business operator 12. The user 14 can download and save the electronic document 100 related to himself / herself to the user terminal 5 by accessing the first server 2 from the user terminal 5 based on the notified address information 101. In the following description, the electronic document saved in the user terminal 5 is referred to as an electronic document 200 to distinguish it from the electronic document 100 stored in the first server 2. For example, in the case of the user 14's job hunting or job hunting, the user 14 can submit the electronic document 200 to the user business operator 13, which is the company where the user 14 will be employed or will be transferred to, by sending the electronic document 200 saved in the user terminal 5 to the operation terminal 4.

[0025] The operation terminal 4 is a PC, tablet, smartphone, or the like, operated by a user organization 13 that uses the electronic document 200. The user organization 13 can request the second server 3 to execute an authenticity determination process for determining whether the electronic document 200 received from the user terminal 5 has been tampered with. The authenticity determination process executed by the second server 3 will be described in detail later.

[0026] 2 is a diagram showing a simplified configuration of the first server 2. The first server 2 includes a processing unit 21, a storage unit 22, and a communication unit 23. The processing unit 21 includes a processor such as a CPU. The storage unit 22 includes a storage medium such as a HDD, SSD, or semiconductor memory. The communication unit 23 includes a communication module compatible with a communication standard such as IP, and transmits and receives information such as data or commands to and from other servers or terminals via the communication network 6. The storage unit 22 stores an electronic document 100 created by the processing unit 21 at a specified address.

[0027] FIG. 3 is a diagram showing a simplified configuration of the second server 3. The second server 3 includes a processing unit 31, a storage unit 32, and a communication unit 33. The processing unit 31 includes a processor such as a CPU. The storage unit 32 includes a storage medium such as an HDD, an SSD, or a semiconductor memory. The communication unit 33 includes a communication module compatible with a communication standard such as IP, and transmits and receives information such as data or commands to and from other servers or terminals via the communication network 6. The storage unit 32 stores address information 101 and a program 300 received from the first server 2. The processing unit 31 includes a receiving unit 311, a transmitting unit 312, and a determining unit 313 as functions realized by the processor executing the program 300 read from the storage unit 32. Details of the processing contents of each of these units will be described later.

[0028] FIG. 4 is a diagram showing a simplified configuration of the operation terminal 4. The operation terminal 4 includes a processing unit 41, a storage unit 42, a communication unit 43, a display unit 44, an input unit 45, and a camera 46. The processing unit 41 includes a processor such as a CPU. The storage unit 42 includes a storage medium such as a HDD, an SSD, or a semiconductor memory. The communication unit 43 includes a communication module compatible with a communication standard such as IP, and transmits and receives information such as data or commands between other servers or terminals via the communication network 6. The display unit 44 includes a liquid crystal display, an organic EL display, or the like. The input unit 45 includes a mouse, a keyboard, a touch panel, or the like. The storage unit 42 stores the electronic document 200 received from the user terminal 5.

[0029] FIG. 5 is a diagram showing a simplified configuration of the user terminal 5. The user terminal 5 includes a processing unit 51, a storage unit 52, a communication unit 53, a display unit 54, and an input unit 55. The processing unit 51 includes a processor such as a CPU. The storage unit 52 includes a storage medium such as a HDD, an SSD, or a semiconductor memory. The communication unit 53 includes a communication module compatible with a communication standard such as IP, and transmits and receives information such as data or commands between other servers or terminals via the communication network 6. The display unit 54 includes a liquid crystal display, an organic EL display, or the like. The input unit 55 includes a mouse, a keyboard, a touch panel, or the like. The storage unit 52 stores the electronic document 200 received from the first server 2.

[0030] Fig. 6 is a simplified diagram showing an example of an electronic document 200. In the example shown in Fig. 6, the electronic document 200 is a transcript of a user 14 who took a certification test administered by the issuing business entity 12. The electronic document 200 includes performance information 210 indicating the name of the user 14 and the score of the certification test, and a two-dimensional code image 220 in which address information 101 such as a URL related to the electronic document 200 is stored. Note that instead of the two-dimensional code image 220, a one-dimensional code image or text information indicating the address information 101 related to the electronic document 200 may be written.

[0031] Fig. 7 is a sequence diagram showing transmission and reception of information among the first server 2, the second server 3, the operation terminal 4, and the user terminal 5. Fig. 8 is a flowchart showing processing executed by the processing unit 31 of the second server 3 in authenticity determination processing for determining an electronic document 200.

[0032] 7, user terminal 5 transmits information S1 to operation terminal 4. Information S1 includes electronic document 200 stored in storage unit 52. Operation terminal 4 stores the received electronic document 200 in storage unit .

[0033] When the user business entity 13 wishes to know whether the electronic document 200 is genuine and has not been tampered with, or whether it is fraudulent and has been tampered with, the operation terminal 4 transmits information S2 to the second server 3. The information S2 includes a request to execute an authenticity determination process for the electronic document 200 to be determined. The authenticity determination process is a process executed on the website of the second server 3. The legitimate issuing business entity 12 has notified the user business entity 13 in advance of the access address and login password for the website.

[0034] When the receiving unit 311 receives the information S2 including the request to execute the authenticity determination process, the operation terminal 4 starts the authenticity determination program and starts the execution of the authenticity determination process. The authenticity determination process will be described below.

[0035] 8, first, in step SP01, the transmission unit 312 transmits information S3 to the operation terminal 4. The information S3 includes requests to display the electronic document 200 to be determined on the screen of the display unit 44, to start the camera 46, to take a picture of the image 220 included in the displayed electronic document 200 with the camera 46, and to return the address information 101 obtained from the taken image 220 to the second server 3.

[0036] 9 is a simplified diagram showing an example of a display on the screen of the display unit 44. A text message is displayed on the display unit 44, requesting the operator of the operation terminal 4 to display the screen of the electronic document 200 and capture an image 220. In response to the request, the operator operates the input unit 45, whereby the electronic document 200 read from the storage unit 42 is displayed on the screen of the display unit 44. When the operator captures the image 220 included in the electronic document 200 with the camera 46, the operation terminal 4 transmits information S4 to the second server 3. The information S4 includes the address information 101 obtained from the image 220.

[0037] When the receiving unit 311 receives the information S4 from the operation terminal 4 (step SP02: YES), the determining unit 313 next determines in step SP03 whether the address information 101 included in the received information S4 is authentic. The storage unit 32 stores a plurality of authentic address information 101 received from the first server 2. If the address information 101 included in the information S4 matches any of the plurality of address information 101 stored in the storage unit 32, the determining unit 313 determines that the address information 101 included in the information S4 is authentic (i.e., the electronic document 200 to be determined has not been tampered with). On the other hand, if the address information 101 included in the information S4 does not match any of the plurality of address information 101 stored in the storage unit 32, the determining unit 313 determines that the address information 101 included in the information S4 is not authentic (i.e., the electronic document 200 to be determined has been tampered with).

[0038] If the address information 101 included in information S4 is legitimate (step SP03: YES), then in step SP04, the sending unit 312 sends information S5 including a reply request for the electronic document 100 corresponding to the address information 101 to the first server 2, the receiving unit 311 receives information S6 including the electronic document 100 from the first server 2, and the sending unit 312 sends information S7 including the legitimate determination result to the operation terminal 4. In this case, information S7 includes the electronic document 100 (i.e. the legitimate electronic document 100 stored in the first server 2).

[0039] 10 is a simplified diagram showing an example of the display on the screen of the display unit 44 when the operation terminal 4 receives information S7 including a genuineness determination result. The electronic document 200 to be determined is displayed in the left half area of ​​the screen. A text message is displayed above the electronic document 200, indicating that the electronic document has not been tampered with. In addition, the right half area of ​​the screen shows a genuine electronic document 100 stored in the first server 2. A text message is displayed above the electronic document 100, indicating that the electronic document is a genuine electronic document stored in the first server 2.

[0040] If the address information 101 included in the information S4 is not legitimate (step SP03: NO), then in step SP05, the transmission unit 312 transmits information S7 including the fraud determination result to the operation terminal 4.

[0041] 11 is a simplified diagram showing an example of the display on the screen of the display unit 44 when the operation terminal 4 receives information S7 including the fraud determination result. The screen shows the electronic document 200 to be determined, and above the electronic document 200 is displayed a text message indicating that the electronic document has been tampered with.

[0042] According to this embodiment, the electronic document 100 includes address information 101 related to the electronic document 100. The operation terminal 4 acquires the address information 101 included in the electronic document 200 to be judged, which is displayed on the screen of the display unit 44, and transmits it to the second server 3. The second server 3 judges the authenticity of the electronic document 200 to be judged based on whether the address information 101 received from the operation terminal 4 is authentic or not. Therefore, it is possible to judge the authenticity of the electronic document 200 by a simple process of judging whether the address information 101 included in the electronic document 200 to be judged is authentic or not. Even if the address information 101 of the electronic document 200 is forged and the operation terminal 4 accesses the forged address, and the first server 2 is forged so as to transmit the tampered electronic document 200 to the operation terminal 4, the forged address does not match any of the multiple authentic address information 101 stored in the storage unit 32, so it is possible to correctly judge that the electronic document 200 is not authentic.

[0043] Furthermore, according to this embodiment, the operation terminal 4 acquires the address information 101 by photographing the image 220 included in the electronic document 200 to be judged, which is displayed on the screen of the display unit 44, with the camera 46. Therefore, it is possible to acquire the address information 101 included in the electronic document 200 to be judged by the simple process of photographing the image 220 with the camera 46. Even if the electronic document 200 to be judged, which is displayed on the screen of the display unit 44, is printed on paper and submitted to the user organization 13, it is possible to acquire the address information 101 by the same simple process as above, by photographing the image 200 printed on the paper with the camera 46.

[0044] Furthermore, according to this embodiment, if the address information 101 received from the operation terminal 4 is legitimate, the second server 3 transmits the legitimate electronic document 100 corresponding to the address information 101 to the operation terminal 4, and displays the legitimate electronic document 100 on the screen of the display unit 44 of the operation terminal 4. This allows the operator of the operation terminal 4 to easily confirm that the electronic document 200 to be judged has not been tampered with, by comparing the electronic document 200 to be judged displayed on the screen with the legitimate electronic document 100. [Explanation of symbols]

[0045] 1 Authenticity determination system 2. First Server 3. Second server (authentication device) 4 Operation terminal 31 Processing section 44 Display section 46 Camera 12 Issuer 13 User company 100,200 electronic documents 101 Address Information 300 Programs 311 Receiving unit 312 Transmitter 313 Judgment section

Claims

1. a first server that creates and stores electronic documents; a second server that is managed by an issuer of the electronic document and that manages address information indicating an address at which the electronic document is stored; an operation terminal operated by a user who uses the electronic document; Equipped with the electronic document includes the address information relating to the electronic document; The operation terminal transmits, to the second server, a request to execute an authenticity determination process for the electronic document to be determined; In the authenticity determination process, the second server transmits, to the operation terminal, a request for returning the address information included in the electronic document to be judged that is displayed on a screen of the operation terminal; the operation terminal acquires the address information included in the electronic document to be judged that is displayed on the screen, and transmits the address information to the second server; the second server determines the authenticity of the electronic document to be determined based on whether the address information received from the operation terminal is legitimate. Authenticity determination system.

2. the electronic document includes the address information relating to the electronic document as an image; the operation terminal acquires the address information by photographing, with a camera, the image included in the electronic document to be judged that is being displayed on the screen; The authenticity determination system according to claim 1 .

3. When the address information received from the operation terminal is legitimate, the second server transmits a legitimate electronic document corresponding to the address information to the operation terminal and displays the legitimate electronic document on the screen of the operation terminal. The authenticity determination system according to claim 2 .

4. An authenticity determination device that is managed by an issuer of an electronic document, manages address information indicating an address at which the electronic document is stored, and determines the authenticity of the electronic document, The device includes a receiving unit, a transmitting unit, and a determining unit, the electronic document includes the address information relating to the electronic document; The receiving unit receives a request to execute an authenticity determination process for an electronic document to be determined from an operation terminal operated by a user who uses the electronic document to be determined; In the authenticity determination process, The transmission unit transmits, to the operation terminal, a request for reply to the address information included in the electronic document to be judged that is displayed on a screen of the operation terminal; The receiving unit receives the address information included in the electronic document to be judged that is displayed on the screen from the operation terminal, the determination unit determines the authenticity of the electronic document to be determined based on whether the address information received from the operation terminal is legitimate. Authenticity determination device.

5. An information processing device that is managed by an issuer of an electronic document, manages address information indicating an address where the electronic document is stored, and includes an authenticity determination device that determines the authenticity of the electronic document, functioning as a receiving means, a transmitting means, and a determining means; the electronic document includes the address information relating to the electronic document; The receiving means receives a request to execute an authenticity determination process for the electronic document to be determined from an operation terminal operated by a user who uses the electronic document to be determined, In the authenticity determination process, The sending means sends, to the operation terminal, a request for reply to the address information included in the electronic document to be judged that is displayed on a screen of the operation terminal; The receiving means receives the address information included in the electronic document to be judged that is displayed on the screen from the operation terminal; the determination means determines the authenticity of the electronic document to be determined based on whether the address information received from the operation terminal is legitimate or not. program.

6. An authenticity determination method executed by an authenticity determination device that is managed by an issuer of an electronic document, manages address information indicating an address at which the electronic document is stored, and determines the authenticity of the electronic document, comprising: the electronic document includes the address information relating to the electronic document; receiving a request for executing an authenticity determination process for the electronic document to be determined from an operation terminal operated by a user who uses the electronic document to be determined; In the authenticity determination process, Transmitting a request for returning the address information contained in the electronic document to be judged, which is displayed on a screen of the operation terminal, to the operation terminal; receiving, from the operation terminal, the address information included in the electronic document to be judged that is being displayed on the screen; determining whether the address information received from the operation terminal is authentic or not, and Authenticity determination method.

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