code: public com.squareup.okhttp.Call getPingAsync(final ApiCallback<String> callback) throws ApiException {
  
          com.squareup.okhttp.Call call = getPingValidateBeforeCall(callback);
          Type localVarReturnType = new TypeToken<String>() {
          }.getType();
          apiClient.executeAsync(call, localVarReturnType, callback);
          return call;
      }
docs: Ping route (asynchronously) Ping the ESI routers
  
  @param callback
  The callback to be executed when the API call finishes
  @return The request call
  @throws ApiException
  If fail to process the API call, e.g. serializing the request
  body object