How to convet .p8 file to .PKCS8 file to generate JWT Token.

Downloaded authentication token signing key in .p8 format. I want convert .p8 file into PKCS8 format file to generate JWT Token for token-based authnection to APNS. Plese help how to convert it.

How to convet .p8 file to .PKCS8 file to generate JWT Token.
 
 
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