code: def _format_config(config, prefix=""):
      from dvc.utils.flatten import flatten
  
      for key, value in flatten(config).items():
          yield f"{prefix}{key}={value}"
  
imports: import argparse
  import os
  from funcy import set_in
  from dvc.cli import formatter
  from dvc.cli.command import CmdBaseNoRepo
  from dvc.cli.utils import append_doc_link
  from dvc.log import logger
  from dvc.ui import ui
label_desc: Use image node_id 9 for calling the CmdConfig obj's underlying member method code with example usage: obj._format_config(config, prefix) without return types