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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 authenticate(self, req, resp, resource):
 """ Extract auth token from request `authorization` header, decode jwt token, verify configured claims and return either a ``user`` object if successful else raise an `falcon.HTTPUnauthoried exception` """

        payload = self._decode_jwt_token(req)
        user = self.user_loader(payload)
        if not user:
            raise falcon.HTTPUnauthorized(
                description='Invalid JWT Credentials')

        return user