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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_group_cached_perms(self):
 """ Set group cache. """

        if not self.group:
            return {}
        perms = Permission.objects.filter(
            group=self.group,
        )
        group_permissions = {}
        for perm in perms:
            group_permissions[(
                perm.object_id,
                perm.content_type_id,
                perm.codename,
                perm.approved,
            )] = True
        return group_permissions