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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 decode_path(file_path):
 """Turn a path name into unicode."""

    if file_path is None:
        return
    if isinstance(file_path, six.binary_type):
        file_path = file_path.decode(sys.getfilesystemencoding())
    return file_path