docs: def _roads_extract(resp):
      """Extracts a result from a Roads API HTTP response."""
  
      try:
          j = resp.json()
      except:
          if resp.status_code != 200:
              raise googlemaps.exceptions.HTTPError(resp.status_code)
  
          raise googlemaps.exceptions.ApiError("UNKNOWN_ERROR",
                                               "Received a malformed response.")
  
      if "error" in j:
          error = j["error"]
          status = error["status"]
  
          if status == "RESOURCE_EXHAUSTED":
              raise googlemaps.exceptions._OverQueryLimit(status,
                                                          error.get("message"))
  
          raise googlemaps.exceptions.ApiError(status, error.get("message"))
  
      if resp.status_code != 200:
          raise googlemaps.exceptions.HTTPError(resp.status_code)
  
      return j