Signature header of RESTful API


I am now testing the DUO RESTful API, I have read from the web side, I need to convert the below header to ‘HMAC-SHA1’ format by using the Secret key. May I ask are there any web site can convert it to HMAC-SHA1 format? Because I want to try the RESTful API in some tools fiest such as SOAPUI/ POSTMAN before start programming.
Many thanks for your help.

Mon, 28 Jan 2019 14:29:18 -0000
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