Counting the occurrences of a character in each element of a list

Question

     lst = ['10010001','01101001']

我需要计算每个元素中数字“1”出现的次数

Answer 1

for element in lst:
    print element.count("1")

Answer 2

>>> lst = ['10010001','01101001']
>>> [l.count('1') for l in lst]
[3, 4]

Answer 3

from collections import Counter
num_of_1s = [Counter(item)['1'] for item in lst]