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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 target_str_to_list(target_str):
 """ Parses a targets string into a list of individual targets. """

    new_list = list()
    for target in target_str.split(','):
        target = target.strip()
        target_list = target_to_list(target)
        if target_list:
            new_list.extend(target_list)
        else:
            LOGGER.info("{0}: Invalid target value".format(target))
            return None
    return list(collections.OrderedDict.fromkeys(new_list))