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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 cc(filename: 'input source file', output: 'output file name. default to be replacing input file\'s suffix with ".py"' = None, name: 'name of language' = 'unname'):
 """ rbnf source code compiler. """


    lang = Language(name)

    with Path(filename).open('r') as fr:
        build_language(fr.read(), lang, filename)

    if not output:
        base, _ = os.path.splitext(filename)

        output = base + '.py'
    lang.dump(output)