code: def _try_switches(self, lines, index):
          
          for s in self._switches:
              s.switch(lines, index)
docs: For each switch in the Collector object, pass a list of string,
          representing lines of text in a file, and an index to the current
          line to try to flip the switch. A switch will only flip on if the line
          passes its 'test_on' method, and will only flip off if the line
          passes its 'test_off' method.
  
          :param lines: List of strings, usually the lines in a text file
          :param index: Number index pointing to the current line