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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 _lower_if_str(item):
 """ Try to convert item to lowercase, if it is string. Args: item (obj):
 Str, unicode or any other object. Returns: obj: ``item.lower()`` if `item` is ``str`` or ``unicode``, else just \ `item` itself. """

    # python 2 / 3 shill
    try:
        string_type = basestring
    except NameError:
        string_type = str

    if isinstance(item, string_type):
        return item.lower()

    return item