但他无法满足当首字母相同时，按第二个字母排序

但他无法满足当首字母相同时，按第二个字母排序，现在应该修改哪里实现这道题目

with open('test.txt') as f:
    lines = f.readlines()
    print(list(map(lambda x: x.strip('\n'), lines)))
    lines = list(map(lambda x: x.strip('\n'), lines))
    lines.sort(key=lambda x: x[::-1])
    print(lines)

data = ['a', 'abc', 'afasf', 'fasdf', 'faseqe', 'fasdf', 'fasdf', 'fasdf', 'fasdf', 'a1']
data.sort(key=lambda x: x[::-1])
print(data)

#新建test.txt并插入
# with open('test.txt','w') as f:
#     f.write('America umbrella grandma grandpa gab grab')
#读取test.txt
with open('test.txt','r') as f:
    lines = f.readlines()
    list1 = lines[0].split()
    list2 = []
    for i in list1:
        list2.append(i[::-1])
    list2.sort()
#写入a.txt
with open('a.txt','a+') as f1:
    counts = {}
    for i in list1:
        if i not in counts:
            counts[i] = 1
        else:
            counts[i] += 1
    counts1 = sorted(counts.items(), key=lambda x: x[1], reverse=True)
    for a in list1:
        f1.write(f"{a}\n")


# 排序写入b.txt
with open('b.txt','a+') as f2:
    for i in list2:
        a = i[::-1]
        f2.write(f"{a}\n")