docs: def generate_csv(path, out):
      """\
      Walks through the `path` and generates the CSV file `out`
      """
      known_persons = ()
      with codecs.open(os.path.join(os.path.dirname(__file__), 'person_names.txt'), 'rb', 'utf-8') as f:
          known_persons = set((l.rstrip() for l in f))
      writer = UnicodeWriter(open(out, 'wb'), delimiter=';')
      for cable in cables_from_source(path):
          content = cable.content_body
          if not content:
              continue
          persons = [person for person in known_persons if person in content]
          if persons:
              row = [cable.reference_id]
              row.extend(persons)
              writer.writerow(row)