code: def assertNodeExists(self, path, result_tree):
      self.assertNotEqual(
          TreePath.find_first(result_tree, path),
          None,
          "Path '%s' not found in result tree" % path,
      )
  
imports: from __future__ import absolute_import
  import os
  import unittest
  import tempfile
  from .Compiler import Errors
  from .CodeWriter import CodeWriter
  from .Compiler.TreeFragment import TreeFragment, strip_common_indent
  from .Compiler.Visitor import TreeVisitor, VisitorTransform
  from .Compiler import TreePath
label_desc: Use image node_id 7 for calling the CythonTest obj's underlying member method code with example usage: obj.assertNodeExists(path, result_tree) without return types