code: def _first_three_elements_regexp() -> Pattern[str]:
      num_re = r"[+\-]?(?:0|[1-9]\d*)(?:\.\d*)?(?:[eE][+\-]?\d+)?"
      pat_re = rf"^(?:(\[+)\s*)?({num_re})(?:\s+({num_re})(?:\s+({num_re}))?)?.*?"
      return re.compile(pat_re)
  
imports: import copy
  import re
  from functools import lru_cache
  from typing import Any, Callable, Dict, Mapping, Optional, Pattern, Tuple, Type, TypeVar, Union
  import numpy
  import tensorflow
  import tensorflow_probability
  from packaging.version import Version
  from tabulate import tabulate
  from tensorflow.python.util.object_identity import Reference
  from ..base import AnyNDArray, Parameter
  from ..config import default_summary_fmt
label_desc: Use image node_id 13 for calling a global function with example usage: _first_three_elements_regexp() and returns: re