code: def mock_tracker_for_evaluation(
      example: "Message", model_metadata: Optional["ModelMetadata"]
  ) -> Optional["DialogueStateTracker"]:
      """Generate a mocked tracker for NLU evaluation."""
  
imports: import argparse
  import functools
  import sys
  from typing import Any, Dict, List, Optional, TYPE_CHECKING, Text, Tuple, Union
  import pluggy
  from rasa.cli import SubParsersAction
label_desc: Use image node_id 10 for calling a global function with example usage: mock_tracker_for_evaluation(example, model_metadata) without return types