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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 is_fold_trigger(block):
 """ Checks if the block is a fold trigger. :param block: block to check :return: True if the block is a fold trigger (represented as a node in the fold panel) """

        if block is None:
            return False
        state = block.userState()
        if state == -1:
            state = 0
        return bool(state & 0x04000000)