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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def create_token(self, request, refresh_token=False):
 """Create a JWT Token, using requestvalidator method."""


        if callable(self.expires_in):
            expires_in = self.expires_in(request)
        else:
            expires_in = self.expires_in

        request.expires_in = expires_in

        return self.request_validator.get_jwt_bearer_token(None, None, request)