code: def read_config():
      
      # XXX modifies global state, which is kind of evil
      config = _load_config()
      if config.get(CFG_IGNORE_DEFAULT_RULES[1], False):
          del IGNORE[:]
      if CFG_IGNORE[1] in config:
          IGNORE.extend(p for p in config[CFG_IGNORE[1]] if p)
      if CFG_IGNORE_BAD_IDEAS[1] in config:
          IGNORE_BAD_IDEAS.extend(p for p in config[CFG_IGNORE_BAD_IDEAS[1]] if p)
docs: Read configuration from file if possible.