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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 extract_extension(path):
 """ Reads a file path and returns the extension or None if the path contains no extension. :Parameters: path : str A filesystem path """

    filename = os.path.basename(path)
    parts = filename.split(".")
    if len(parts) == 1:
        return filename, None
    else:
        return ".".join(parts[:-1]), parts[-1]