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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 get_tab(self, tab_name, allow_disabled=False):
 """Returns a specific tab from this tab group. If the tab is not allowed or not enabled this method returns ``None``. If the tab is disabled but you wish to return it anyway, you can pass ``True`` to the allow_disabled argument. """

        tab = self._tabs.get(tab_name, None)
        if tab and tab._allowed and (tab._enabled or allow_disabled):
            return tab
        return None