我列表中有许多空列表，我怎么删除我列表中的空列表

import re

f = open('aa.txt', encoding='utf-8')
txt=[]
ab=[]
for line in f:
txt.append(line.strip())
for i in txt:
a = re.findall('^[1-9].*', i)
ab.append(a)
print(ab)

加个条件判断就行吧

import re

f = open('aa.txt', encoding='utf-8')
txt=[]
ab=[]
for line in f:
    txt.append(line.strip())
for i in txt:
    a = re.findall('^[1-9].*', i)
    if a:
        ab.append(a)
print(ab)