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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 edit_tab(self, index):

 """Activate the edit tab."""


        # Sets focus, shows cursor
        self.setFocus(True)

        # Updates tab index
        self.tab_index = index

        # Gets tab size and shrinks to avoid overlapping tab borders
        rect = self.main.tabRect(index)
        rect.adjust(1, 1, -2, -1)

        # Sets size
        self.setFixedSize(rect.size())

        # Places on top of the tab
        self.move(self.main.mapToGlobal(rect.topLeft()))

        # Copies tab name and selects all
        text = self.main.tabText(index)
        text = text.replace(u'&', u'')
        if self.split_char:
            text = text.split(self.split_char)[self.split_index]

        self.setText(text)
        self.selectAll()

        if not self.isVisible():
            # Makes editor visible
            self.show()