code: def test_entering_directory_on_stdout(self):
      output = run(Output.BUILD_SIMPLE_ECHO, flags="-C$PWD", pipe=True)
      self.assertEqual(
          output.splitlines()[0][:25], "ninja: Entering directory"
      )
  
file_path: ninja/misc/output_test.py
imports: import os
  import platform
  import subprocess
  import sys
  import tempfile
  import unittest
label_desc: Use image node_id 8 for calling the Output obj's underlying member method code with example usage: obj.test_entering_directory_on_stdout() without return types