POST Headers on a specified object in the container.

        :param uri: ``str``
        :param headers: ``dict``

def _header_poster(self, uri, headers):
        """POST Headers on a specified object in the container.

        :param uri: ``str``
        :param headers: ``dict``
        """

        resp = self.http.post(url=uri, body=None, headers=headers)
        self._resp_exception(resp=resp)
        return resp