Append another key to the key sequence represented by this object.

        |Args|

        * ``keyEvent`` (**QKeyEvent**): the key to add.

        |Returns|

        **None**

        |Raises|

        * **QtmacsArgumentError** if at least one argument has an invalid type.

def appendQKeyEvent(self, keyEvent: QtGui.QKeyEvent):
        """
        Append another key to the key sequence represented by this object.

        |Args|

        * ``keyEvent`` (**QKeyEvent**): the key to add.

        |Returns|

        **None**

        |Raises|

        * **QtmacsArgumentError** if at least one argument has an invalid type.
        """
        # Store the QKeyEvent.
        self.keylistKeyEvent.append(keyEvent)

        # Convenience shortcuts.
        mod = keyEvent.modifiers()
        key = keyEvent.key()

        # Add the modifier and key to the list. The modifier is a
        # QFlag structure and must by typecast to an integer to avoid
        # difficulties with the hashing in the ``match`` routine of
        # the ``QtmacsKeymap`` object.
        self.keylistQtConstants.append((int(mod), key))