class_docstr: Fake GRIB file returned by pygrib.open.
class_docstr_tok: ["Fake","GRIB","file","returned","by","pygrib.open","."]
docstr: Fake message.
docstr_tok: ["Fake","message","."]
code: def message(self, msg_num):
      """Fake message."""
      return self._messages[msg_num - 1]
  
imports: import sys
  import unittest
  from datetime import datetime
  from unittest import mock
  import numpy
  from pytest import approx
  from satpy.tests.utils import make_dataid
label_desc: Use image node_id 2 for calling the FakeGRIB obj's underlying member method code with example usage: obj.message(msg_num) and returns: self