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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 normalize_topic(topic):
 """ Get a canonical representation of a Wikipedia topic, which may include a disambiguation string in parentheses. Returns (name, disambig), where "name" is the normalized topic name, and "disambig" is a string corresponding to the disambiguation text or None. """

    # find titles of the form Foo (bar)
    topic = topic.replace('_', ' ')
    match = re.match(r'([^(]+) \(([^)]+)\)', topic)
    if not match:
        return normalize(topic), None
    else:
        return normalize(match.group(1)), 'n/' + match.group(2).strip(' _')