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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 for_category(self, category, context=None):
 """Returns actions list for this category in current application. Actions are filtered according to :meth:`.Action.available`. if `context` is None, then current action context is used (:attr:`context`) """

        assert self.installed(), "Actions not enabled on this application"
        actions = self._state["categories"].get(category, [])

        if context is None:
            context = self.context

        return [a for a in actions if a.available(context)]