Count Values from list in Python

#count duplicte values from list


letters =  ['a','b','c','a','d','c','d','c','a'] #list with duplicate values

list_string = ' '.join([str(elem) for elem in letters]) #convert the list to string join them by space

#count each letter/values of set-list from converted string

for lt in set(letters):
    print('lt : '+lt+' '+str(list_string.count(lt)))