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