def METHOD_NAME(data):
  """Recursively validate all keys in a dictionary."""
  valid = True
  for k, v in data.items():
    valid = validate_yaml_key_format(str(k)) and valid
    if isinstance(v, dict):
      valid = METHOD_NAME(v) and valid
    elif isinstance(v, list):
      for item in v:
        if isinstance(item, dict):
          valid = METHOD_NAME(item) and valid
  return valid