例2.42 遍历文件data2_2.txt 中的所有行，统计每一行中字符的个数
with open('data2_2.txt') as fp:
L1=[];L2=[]
for line in fp:
L1.append(len(line))
L2.append(len(line.strip()))
data = [str(num) + '\t'for num in L2]
print(L1);print(L2)
with open('data2_42.txt','w')as fp2:
fp2.writelines(data)
print("学号：3008")结果如下
