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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 format_item(self, action, item_type='actor'):
 """ Returns a formatted dictionary for an individual item based on the action and item_type. """

        obj = getattr(action, item_type)
        return {
            'id': self.get_uri(action, obj),
            'url': self.get_url(action, obj),
            'objectType': ContentType.objects.get_for_model(obj).name,
            'displayName': text_type(obj)
        }