1. 文件a.txt内容：每一行内容分别为商品名字，价钱，个数。
apple 10 3
tesla 100000 1
mac 3000 2
lenovo 30000 3
chicken 10 3
通过代码，将其构建成这种数据类型：[{'name':'apple','price':10,'amount':3},{'name':'tesla','price':1000000,'amount':1}......] 并计算出总价钱。
li = []
with open('a.txt', encoding='utf-8', mode='r') as f1:
for i in f1:
l2 = i.strip().split()
dic = {'name':l2[0], 'price':l2[1], 'amount':l2[2]}
li.append(dic)
print(li)
sum = 0
for j in li:
sum = sum + int(j['price']) * int(j['amount'])
print(sum)
优化拓展
name_list = ['name', 'price', 'amount']
li = []
with open('a.txt', encoding='utf-8', mode='r') as f1:
for i in f1:
l2 = i.strip().split()
# dic = {}
# for j in range(len(l2)):
# dic[name_list[j]] = l2[j]
dic = dict(zip(name_list, l2)) # 前面三句可以优化成这一句，易读性也更强
li.append(dic)
print(li)
sum = 0
for k in li:
sum = sum + int(k['price']) * int(k['amount'])
print(sum)
2，有如下文件：
-------
alex是老男孩python发起人，创建人。
alex其实是人妖。
谁说alex是sb？
你们真逗，alex再牛逼，也掩饰不住资深屌丝的气质。
----------
将文件中所有的alex都替换成大写的SB。
import os
with open('alex.txt', encoding='utf-8', mode='r') as f1,\
open('SB.txt', encoding='utf-8', mode='w') as f2:
for i in f1:
print(i)
new_i = i.replace('alex', 'SB')
f2.write(new_i)
os.remove('alex.txt')
os.rename('SB.txt', 'alex.txt')
3. 文件a1.txt内容：每一行内容分别为商品名字，价钱，个数。
文件内容：
name:apple price:10 amount:3 year:2012
name:tesla price:100000 amount:1 year:2013
通过代码，将其构建成这种数据类型：
[{'name':'apple','price':10,'amount':3},
{'name':'tesla','price':1000000,'amount':1}......]
并计算出总价钱。
lis = []
dic = {}
with open('a1.txt', encoding='utf-8', mode='r') as f2:
for i in f2:
li = i.strip().split()
for j in li:
KeyVal = j.split(':')
dic.setdefault(KeyVal[0], KeyVal[1])
lis.append(dic)
dic = {}
print(lis)
sum = 0
for k in lis:
sum =sum + int(k['amount'])*int(k['price'])
print(sum)
lis = []
dic = {}
with open('a1.txt', encoding='utf-8', mode='r') as f2:
for i in f2:
li = i.strip().split()
for j in li:
KeyVal = j.split(':')
dic.setdefault(KeyVal[0], KeyVal[1])
lis.append(dic)
dic = {}
print(lis)
4,文件a2.txt内容：每一行内容分别为商品名字，价钱，个数。
文件内容：
序号 部门 人数 平均年龄 备注
1 python 30
26 单身狗
2 Linux 26
30 没对象
3 运营部 20
24 女生多
通过代码，将其构建成这种数据类型：
[{'序号':'1','部门':Python,'人数':30,'平均年龄':26,'备注':'单身狗'},
......]
li = []
with open('a2.txt',encoding='utf-8')as f1:
key = f1.readline().strip().split()
for i in f1:
val = i.strip().split()
dic = dict(zip(key,val))
li.append(dic)
print(li)