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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 _prohibited(from_op, to_op):
    "Determines if from_op is allowed to be mutated to to_op."
    # 'not' can only be removed but not replaced with
    # '+', '-' or '~' b/c that may lead to strange results
    if from_op is UnaryOperators.Not:
        if to_op is not UnaryOperators.Nothing:
            return True

    # '+1' => '1' yields equivalent mutations
    if from_op is UnaryOperators.UAdd:
        if to_op is UnaryOperators.Nothing:
            return True

    return False