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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 clean_asciidoc(text):
 r""" Transform asciidoc text into ASCII text that NL parsers can handle TODO: Tag lines and words with meta data like italics, underlined, bold, title, heading 1, etc '"Hello" "world"!' """

    text = re.sub(r'(\b|^)[\[_*]{1,2}([a-zA-Z0-9])', r'"\2', text)
    text = re.sub(r'([a-zA-Z0-9])[\]_*]{1,2}', r'\1"', text)
    return text