code: def unregister_algo_meta(algo_name: str) -> None:
      """
      Unregister a custom algorithm.
      If it does not exist, do nothing.
      """
      algos = [
          algo
          for algo in _load_custom_config()
          if algo.name != algo_name
      ]
      _save_custom_config(algos)
  
file_path: nni/nni/tools/package_utils/config_manager.py
imports: from __future__ import annotations
  from collections import defaultdict
  import yaml
  from nni.runtime.config import get_builtin_config_file, get_config_file
  from .common import AlgoMeta
label_desc: Use image node_id 4 for calling a global function with example usage: unregister_algo_meta(algo_name) without return types