code: def test_multi_file_output(self):
      a_pyx = os.path.join(self.src_dir, "a.pyx")
      a_c = a_pyx[:-4] + ".c"
      a_h = a_pyx[:-4] + ".h"
      a_api_h = a_pyx[:-4] + "_api.h"
      open(a_pyx, "w").write(
          "cdef public api int foo(int x): return x\n"
      )
      self.fresh_cythonize(a_pyx, cache=self.cache_dir)
      expected = [a_c, a_h, a_api_h]
      for output in expected:
          self.assertTrue(os.path.exists(output), output)
          os.unlink(output)
      self.fresh_cythonize(a_pyx, cache=self.cache_dir)
      for output in expected:
          self.assertTrue(os.path.exists(output), output)
  
file_path: catboost/contrib/tools/cython/Cython/Build/Tests/TestCyCache.py
imports: import difflib
  import glob
  import gzip
  import os
  import tempfile
  import Cython.Build.Dependencies
  import Cython.Utils
  from Cython.TestUtils import CythonTest
label_desc: Use image node_id 6 for calling the TestCyCache obj's underlying member method code with example usage: obj.test_multi_file_output() without return types