def loadMethod(self, method):
        """
        Given a method of a C{TestCase} that represents a test, return a
        C{TestCase} instance for that test.
        """
        if not isinstance(method, types.MethodType):
            raise TypeError("%r not a method" % (method,))
        return self._makeCase(method.im_class, _getMethodNameInClass(method))

        Given a method of a C{TestCase} that represents a test, return a
        C{TestCase} instance for that test.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/trial/runner.py