Access variable attributes inside dplyr user defined function

I'm trying to create a function to compute weighted averages from survey data, where the variable name is taken from a variable attribute. I have imported a dataset where each variable already has a label Here's a reproducible example:

random_df<- data.frame(replicate(5,sample(0:1,10,rep=TRUE)))
attr(random_df$X1, 'label') <-"Age"
attr(random_df$X2, 'label') <-"Gender"
attr(random_df$X3, 'label') <-"Occupation"
attr(random_df$X4, 'label') <-"Nationality"
attr(random_df$X5, 'label') <-"Education"

I would like to create a function that computes weighted averages and names the variables from the label. I tried the following

my_function<- function(var, ...){
  var<-enquo(var)
  group_var <- enquos(...)
  df <-random_df

label<-attr(df$!!var,'label')

  df %>%
    filter(!is.na(!!var))%>%
    group_by(!!!group_var) %>%
    count(!!var) %>%
    mutate(freq=n/sum(n)) %>%
    mutate(!!label:=percent(freq)) 

}

This however gives me an error Error: unexpected '!' in:" label<-attr(df$!". Would anyone know how to fix the code?