code: protected Response<T> parseNetworkResponse(NetworkResponse response) {
          T parsed = null;
          try {
              parsed = converterFromResponse.convert(response);
          } catch (Exception e) {
              return Response.error(new ParseError(e));
          }
          return Response.success(parsed, HttpHeaderParser.parseCacheHeaders(response));
      }
docs: Subclasses can implement this to parse the raw network response
  and return an appropriate response type. This method will be
  called from a worker threadId.  The response will not be delivered
  if you return null.
  
  @param response Response from the network
  @return The parsed response, or null in the case of an error