def get(self):
        """
        Get the underlying attribute value and issue a deprecation warning.
        """
        # This might fail if the deprecated thing is a module inside a package.
        # In that case, don't emit the warning this time.  The import system
        # will come back again when it's not an AttributeError and we can emit
        # the warning then.
        result = getattr(self.module, self.__name__)
        message = _getDeprecationWarningString(self.fqpn, self.version,
            DEPRECATION_WARNING_FORMAT + ': ' + self.message)
        warn(message, DeprecationWarning, stacklevel=3)
        return result

        Get the underlying attribute value and issue a deprecation warning.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/deprecate.py