Receive data with operation code.

        control_frame: a boolean flag indicating whether to return control frame
        data, defaults to False

        return  value: tuple of operation code and string(byte array) value.

def recv_data(self, control_frame=False):
        """
        Receive data with operation code.

        control_frame: a boolean flag indicating whether to return control frame
        data, defaults to False

        return  value: tuple of operation code and string(byte array) value.
        """
        opcode, frame = self.recv_data_frame(control_frame)
        return opcode, frame.data