code: def test_basic(self):
      F = self.fragment("x = 4")
      T = F.copy()
      self.assertCode("x = 4", T)
  
file_path: catboost/contrib/tools/cython/Cython/Compiler/Tests/TestTreeFragment.py
imports: from Cython.TestUtils import CythonTest
  from Cython.Compiler.TreeFragment import *
  from Cython.Compiler.Nodes import *
  from Cython.Compiler.UtilNodes import *
  import Cython.Compiler.Naming
label_desc: Use image node_id 1 for calling the TestTreeFragments obj's underlying member method code with example usage: obj.test_basic() without return types