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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, token, use_token=True, mount_point=DEFAULT_MOUNT_POINT):
 """Login using GitHub access token. Supported methods: POST: /auth/{mount_point}/login. Produces: 200 application/json :param token: GitHub personal API token. :type token: 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 login request. :rtype: dict """

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