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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 _http(self):
 """Getter for object used for HTTP transport. :rtype: :class:`~requests.Session` :returns: An HTTP object. """

        if self._http_internal is None:
            self._http_internal = google.auth.transport.requests.AuthorizedSession(
                self._credentials
            )
        return self._http_internal