docs: def ensure_segment_table(connection):
      """Ensures that the DB represented by connection posses a segment table.
      If not, creates one and prints a warning to stderr"""
  
      count = connection.cursor().execute("SELECT count(*) FROM sqlite_master WHERE name='segment'").fetchone()[0]
  
      if count == 0:
          print >>sys.stderr, "WARNING: None of the loaded files contain a segment table"
          theClass  = lsctables.TableByName['segment']
          statement = "CREATE TABLE IF NOT EXISTS segment (" + ", ".join(map(lambda key: "%s %s" % (key, ligolwtypes.ToSQLiteType[theClass.validcolumns[key]]), theClass.validcolumns)) + ")"
  
          connection.cursor().execute(statement)