@property<EOL><INDENT>def expires_at(self):<DEDENT>
return self._expires_at<EOL>
Gets the expires_at of this ObtainTokenResponse.
The date when access_token expires, in [ISO 8601](http://www.iso.org/iso/home/standards/iso8601.htm) format.

:return: The expires_at of this ObtainTokenResponse.
:rtype: str