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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 listify(x, none_value=[]):
 """Make a list of the argument if it is not a list."""


    if isinstance(x, list):
        return x
    elif isinstance(x, tuple):
        return list(x)
    elif x is None:
        return none_value
    else:
        return [x]