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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 is_enabled(self):
 """Returns `True` when rule enabled. :rtype: bool """

        if self.name in settings.exclude_rules:
            return False
        elif self.name in settings.rules:
            return True
        elif self.enabled_by_default and ALL_ENABLED in settings.rules:
            return True
        else:
            return False