def checkLoop(self, over):
        frame = over
        while frame: #while not beyond top
            if frame is self:
                return True #loop found
            else:
                frame = frame.over #keep going up outline
        return False #no loop
Check if attachment to over param would create loop
dataset/ETHPy150Open ioflo/ioflo/ioflo/base/framing.py/Frame.checkLoop