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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 _format_str(string):
 """Attempt fast string handing by decoding directly into an array."""

    if isinstance(string, _STRTYPES):
        if _IS_PYTHON3:
            array = _array.array('I')
            array.frombytes(string.encode(_utf32_codec))
        else: # Python 2
            if isinstance(string, unicode):
                array = _array.array(b'I')
                array.fromstring(string.encode(_utf32_codec))
            else:
                array = _array.array(b'B')
                array.fromstring(string)
        return array
    return string