Phyton SDK and JWT "error_description":"OpenSSL unable to verify data

Anybody that could help me to get this solve please? 

I'm getting the error "error":"invalid_grant","error_description":"OpenSSL unable to verify data:

I'm using Python SDK and I'm trying to authenticate with JWT. 

def login(self, enterprise_id, user_id, rsa_private_key_file_sys_path, rsa_private_key_passphrase):

        self.jwt_auth = JWTAuth(client_id=self.client_id,

                                client_secret=self.client_secret,

                                enterprise_id=enterprise_id,

                                jwt_key_id=JWT_KEY_ID,

                                rsa_private_key_file_sys_path=rsa_private_key_file_sys_path,

                                rsa_private_key_passphrase=rsa_private_key_passphrase,

                                store_tokens=self.store_tokens)

                                # box_device_name='test')

        self.access_token = self.jwt_auth.authenticate_app_user(User(None, user_id))

        # self.access_token = self.jwt_auth.authenticate_instance()

        self.client = Client(self.jwt_auth)