输入代码：
local tempvar"index_aggregate coverage_breadth usage_depth payment insurance monetary_fund investment credit credit_investigation digitization_level"
foreach v of varlist`tempvar'{
      gen L_`v'=L.`v'
      bys year: egen mean_`v'=mean(`v')
      xtset prov_code year,yearly
      gen D_mean_`v'=D.mean_`v'
      gen bartik_`v'=D_mean_`v'*L_`v'
}
显示varlist required r(100);  挨个把每一条代码输进去，显示的又是invalid syntax
r(198);
是哪里出问题了呢？对比了参考代码，好像没有错误，请大佬们帮忙看看哇！