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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 Not(x, simplify=True):
 """Expression negation operator If *simplify* is ``True``, return a simplified expression. """

    x = Expression.box(x).node
    y = exprnode.not_(x)
    if simplify:
        y = y.simplify()
    return _expr(y)