Сформировать словарь в котором ключи - цифры, значения - количество цифр в строке

def count_it(sequence):
    x = {}
    for i in sequence:
        x[i] = x.get(i,0) +1
    return x

def count_it(sequence):
    a = list(sequence)
    b = sorted(a, key = a.count, reverse = True)
    x = {}
    for i in b:
        x[i] = x.get(i,0) +1
    return x

from collections import Counter
 
 
def count_it(s):
    result = Counter(map(int, s)).most_common(3)
    return dict(result)
    
assert {3: 8, 1: 7, 5: 7} == count_it("123456789012133288776655353535353441111")

from collections import defaultdict
from heapq import nlargest
from operator import itemgetter
 
 
def count_it(s):
    counter = defaultdict(int)
    for digit in map(int, s):
        counter[digit] += 1
    return dict(nlargest(3, counter.items(), key=itemgetter(1)))
    
assert {3: 8, 1: 7, 5: 7} == count_it("123456789012133288776655353535353441111")

from heapq import nlargest
from operator import itemgetter
 
 
def count_it(s):
    result = [0] * 10
    digits = map(int, s)
    for digit in digits:
        result[digit] += 1
    return dict(nlargest(3, enumerate(result), key=itemgetter(1)))
    
assert {3: 8, 1: 7, 5: 7} == count_it("123456789012133288776655353535353441111")