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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_tab(self, tab_idx):

 """Change tab focus"""

        for i in range(self.tab_widget.count()):
            self.tab_widget.setTabEnabled(i, False)
        self.tab_widget.setTabEnabled(tab_idx, True)
        self.tab_widget.setCurrentIndex(tab_idx)