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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 login(self, role, jwt, use_token=True, mount_point=DEFAULT_MOUNT_POINT):
 """Login to retrieve a Vault token via the GCP auth method. This endpoint takes a signed JSON Web Token (JWT) and a role name for some entity. It verifies the JWT signature with Google Cloud to authenticate that entity and then authorizes the entity for the given role. Supported methods: POST: /auth/{mount_point}/login. Produces: 200 application/json :param role: The name of the role against which the login is being attempted. :type role: str | unicode :param jwt: A signed JSON web token :type jwt: str | unicode :param use_token: if True, uses the token in the response received from the auth request to set the "token" attribute on the the :py:meth:`hvac.adapters.Adapter` instance under the _adapater Client attribute. :type use_token: bool :param mount_point: The "path" the method/backend was mounted on. :type mount_point: str | unicode :return: The JSON response of the request. :rtype: dict """

        params = {
            'role': role,
            'jwt': jwt,
        }
        api_path = '/v1/auth/{mount_point}/login'.format(mount_point=mount_point)
        response = self._adapter.login(
            url=api_path,
            use_token=use_token,
            json=params,
        )
        return response