code: func (wxa *MiniProgram) GetAnalysisDailyRetain(beginDate, endDate string) (result ResAnalysisRetain, err error) {
  	return wxa.getAnalysisRetain(getAnalysisDailyRetainURL, beginDate, endDate)
  }
docs: // GetAnalysisDailyRetain 获取用户访问小程序日留存