class_docstr: Test GRIB Reader.
class_docstr_tok: ["Test","GRIB","Reader","."]
docstr: Test basic init with no extra parameters.
docstr_tok: ["Test","basic","init","with","no","extra","parameters","."]
code: def test_init(self):
      """Test basic init with no extra parameters."""
      from satpy.readers import load_reader
  
      with mock.patch("satpy.readers.grib.pygrib") as pg:
          pg.open.return_value = FakeGRIB()
          r = load_reader(self.reader_configs)
          loadables = r.select_files_from_pathnames(
              [
                  "gfs.t18z.sfluxgrbf106.grib2",
              ]
          )
          assert len(loadables) == 1
          r.create_filehandlers(loadables)
          # make sure we have some files
          assert r.file_handlers
  
imports: import os
  import sys
  from unittest import mock
  import numpy
  import pytest
  import xarray
  from satpy.dataset import DataQuery
label_desc: Use image node_id 5 for calling the TestGRIBReader obj's underlying member method code with example usage: obj.test_init() without return types