code: def db_connection():
      global _db_connection
      if _db_connection is None:
          os.makedirs(CACHEDB.rsplit(os.sep, 1)[0], exist_ok=True)
          _db_connection = sqlite3.connect(CACHEDB)
          if DEBUG >= 7:
              _db_connection.set_trace_callback(print)
      return _db_connection
  
imports: from __future__ import annotations
  import os, functools, platform, time, re, contextlib, operator, hashlib, pickle, sqlite3, cProfile, pstats, tempfile, pathlib, string, ctypes
  from urllib import request
  from tqdm import tqdm
  from typing import Dict, Tuple, Union, List, ClassVar, Optional, Iterable, Any, TypeVar, TYPE_CHECKING, Callable, Sequence
label_desc: Use image node_id 25 for calling a global function with example usage: db_connection() and returns: _db_connection