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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 unwraplist(v):
 """ LISTS WITH ZERO AND ONE element MAP TO None AND element RESPECTIVELY """

    if is_list(v):
        if len(v) == 0:
            return None
        elif len(v) == 1:
            return unwrap(v[0])
        else:
            return unwrap(v)
    else:
        return unwrap(v)