class_docstr: The GzipFile class simulates most of the methods of a file object with
  the exception of the truncate() method.
  
  This class only supports opening files in binary mode. If you need to open a
  compressed file in text mode, use the gzip.open() function.
docstr: Last modification time read from stream, or None
docstr_tok: ["Last","modification","time","read","from","stream",",","or","None"]
code: def mtime(self):
      """Last modification time read from stream, or None"""
      return self._buffer.raw._last_mtime
  
imports: import struct, sys, time, os
  import zlib
  import builtins
  import io
  import _compression
label_desc: Use image node_id 3 for calling the GzipFile obj's underlying member method code with example usage: obj.mtime() and returns: self