code: def _create_simple_gzip_header(
      compresslevel: int, mtime=None
  ) -> bytes:
      """
      Write a simple gzip header with no extra fields.
      :param compresslevel: Compresslevel used to determine the xfl bytes.
      :param mtime: The mtime (must support conversion to a 32-bit integer).
      :return: A bytes object representing the gzip header.
      """
      if mtime is None:
          mtime = time.time()
      if compresslevel == _COMPRESS_LEVEL_BEST:
          xfl = 2
      elif compresslevel == _COMPRESS_LEVEL_FAST:
          xfl = 4
      else:
          xfl = 0
      # Pack ID1 and ID2 magic bytes, method (8=deflate), header flags (no extra
      # fields added to header), mtime, xfl and os (255 for unknown OS).
      return struct.pack(
          "<BBBBLBB", 0x1F, 0x8B, 8, 0, int(mtime), xfl, 255
      )
  
imports: import struct, sys, time, os
  import zlib
  import builtins
  import io
  import _compression
label_desc: Use image node_id 5 for calling a global function with example usage: _create_simple_gzip_header(compresslevel, mtime) and returns: struct