def test_processWithData(self):
        """
        L{ProxyRequest.process} should be able to retrieve request body and
        to forward it.
        """
        return self._testProcess(
            b"/foo/bar", b"/foo/bar", b"POST", b"Some content")

        L{ProxyRequest.process} should be able to retrieve request body and
        to forward it.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_proxy.py