code: def _touch_geo_file(prefix):
      geo_fn = (
          prefix
          + "_npp_d20120225_t1801245_e1802487_b01708_c20120226002130255476_noaa_ops.h5"
      )
      open(geo_fn, "w")
      return geo_fn
  
imports: import os
  import unittest
  from contextlib import contextmanager
  from unittest import mock
  import numpy
  import pytest
  from satpy.readers.viirs_atms_sdr_base import DATASET_KEYS
  from satpy.tests.reader_tests.test_hdf5_utils import FakeHDF5FileHandler
label_desc: Use image node_id 2 for calling a global function with example usage: _touch_geo_file(prefix) and returns: geo_fn