code: def normalize_topic(topic):
      
      # 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(' _')
docs: 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.