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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 to_list(obj):
 """ Converts an object into a list if it not an iterable, forcing tuples into lists. Nones are returned unchanged. """

    obj = to_iter(obj)

    if isinstance(obj, type(None)):
        return None
    else:
        return list(obj)