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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 str_to_list( input_str, item_converter=lambda x: x, item_separator=',', list_to_collection_converter=None, ):
 """ a conversion function for list """

    if not isinstance(input_str, six.string_types):
        raise ValueError(input_str)
    input_str = str_quote_stripper(input_str)
    result = [
        item_converter(x.strip())
        for x in input_str.split(item_separator) if x.strip()
    ]
    if list_to_collection_converter is not None:
        return list_to_collection_converter(result)
    return result