class_docstr: Testing the file handler.
class_docstr_tok: ["Testing","the","file","handler","."]
docstr: Test dataset start time stamp.
code: def test_start_time(self):
      """Test dataset start time stamp."""
      assert self.reader.start_time == self.time
  
imports: import datetime
  import unittest
  from unittest import mock
  import numpy
  import pytest
  import xarray
  from pyresample.geometry import AreaDefinition
  from satpy.readers.goes_imager_nc import is_vis_channel
  from satpy.tests.utils import make_dataid
label_desc: Use image node_id 8 for calling the GOESNCBaseFileHandlerTest obj's underlying member method code with example usage: obj.test_start_time() without return types