code: def get_output(script):
      
      if six.PY2:
          logs.warn('Experimental instant mode is Python 3+ only')
          return None
  
      if 'THEFUCK_OUTPUT_LOG' not in os.environ:
          logs.warn("Output log isn't specified")
          return None
  
      if const.USER_COMMAND_MARK not in os.environ.get('PS1', ''):
          logs.warn(
              "PS1 doesn't contain user command mark, please ensure "
              "that PS1 is not changed after The Fuck alias initialization")
          return None
  
      try:
          with logs.debug_time(u'Read output from log'):
              fd = os.open(os.environ['THEFUCK_OUTPUT_LOG'], os.O_RDONLY)
              buffer = mmap.mmap(fd, const.LOG_SIZE_IN_BYTES, mmap.MAP_SHARED, mmap.PROT_READ)
              _skip_old_lines(buffer)
              lines = _get_output_lines(script, buffer)
              output = '\n'.join(lines).strip()
              logs.debug(u'Received output: {}'.format(output))
              return output
      except OSError:
          logs.warn("Can't read output log")
          return None
      except ScriptNotInLog:
          logs.warn("Script not found in output log")
          return None
docs: Reads script output from log.
  
      :type script: str
      :rtype: str | None