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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 add_tab(self, widget):

 """Add tab."""

        self.clients.append(widget)
        index = self.tabwidget.addTab(widget, widget.get_short_name())
        self.tabwidget.setCurrentIndex(index)
        self.tabwidget.setTabToolTip(index, widget.get_filename())
        if self.dockwidget and not self.ismaximized:
            self.dockwidget.setVisible(True)
            self.dockwidget.raise_()
        self.activateWindow()
        widget.notebookwidget.setFocus()