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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_default_classes(self):
 """Returns a list of the default classes for the tab. Defaults to and empty list (``[]``), however additional classes may be added depending on the state of the tab as follows: If the tab is the active tab for the tab group, in which the class ``"active"`` will be added. If the tab is not enabled, the classes the class ``"disabled"`` will be added. """

        default_classes = super(Tab, self).get_default_classes()
        if self.is_active():
            default_classes.extend(CSS_ACTIVE_TAB_CLASSES)
        if not self._enabled:
            default_classes.extend(CSS_DISABLED_TAB_CLASSES)
        return default_classes