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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 del_permission(self, role, name):
 """ revoke authorization of a group """

        if not self.has_permission(role, name):
            return True
        targetGroup = AuthGroup.objects(role=role, creator=self.client).first()
        target = AuthPermission.objects(groups=targetGroup, name=name, creator=self.client).first()
        if not target:
            return True
        target.delete()
        return True