please am getting an error $-$# training performance comparison

models$\_$train$\_$comp$\_$df $=$ pd$.$concat$($

$[$

decision$\_$tree$\_$perf$\_$train.T$,$

decision$\_$tree$\_$tune$\_$perf$\_$train.T$,$

decision$\_$tree$\_$post$\_$perf$\_$train.T$,$

$],$

axis$=1,$

$)$

models$\_$train$\_$comp$\_$df$.$columns $=[$

"Decision Tree sklearn",

"Decision Tree $($Pre$-$Pruning$)",$

"Decision Tree $($Post$-$Pruning$)",$

$]$

print$("$Training performance comparison:"$)$

models$\_$train$\_$comp$\_$df