code: def test_stream_with_flush_is_flushed(self):
      self._setup(delete_flush=False)
      self.assertTrue(hasattr(self.stream, "flush"))
      self.stream.flush.assert_not_called()
      self.report(self.trainer)
      self.stream.flush.assert_called_with()
  
file_path: chainer/tests/chainer_tests/training_tests/extensions_tests/test_print_report.py
imports: import tempfile
  import unittest
  import mock
  from chainer import testing
  from chainer.training import extensions
label_desc: Use image node_id 2 for calling the TestPrintReport obj's underlying member method code with example usage: obj.test_stream_with_flush_is_flushed() without return types