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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 aslist(obj, sep=None, strip=True):
 """ Returns given string separated by sep as list :param obj: :param sep: :param strip: """

    if isinstance(obj, (basestring)):
        lst = obj.split(sep)
        if strip:
            lst = [v.strip() for v in lst]
        return lst
    elif isinstance(obj, (list, tuple)):
        return obj
    elif obj is None:
        return []
    else:
        return [obj]