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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def focus_widget(self, checked=None, w=None):
 """Focus the given widget. Checked is ignored and only used as a slot for QAbstractButton.clicked. :param checked: The checked state of the button that was clicked :type checked: bool :param w: the widget to focus :type w: QtGui.QWidget :returns: None :raises: None """

        if w is None:
            return
        if w.isMinimized():
            w.showNormal()
        else:
            w.show()
        w.activateWindow()
        w.setFocus()