在字典的循环中删除指定的键值

#!usr/bin/python
# -*- coding: utf-8 -*-
# @Time    : 2018/3/14 15:57
# @Author  : 黑咖啡
# @Email   : webaa88@126.com
# @File    : dicttest.py
# @Software: PyCharm


a_dict = {
    'haozhe':{'chengji':'100','age':'11'},
    'ruizhe':{'chengji':'300','age':'11'},
    'yanzi':{'chengji':'90','age':'11'},

          }
print('源字典:',a_dict)
for key in list(a_dict.keys()):
    
    if a_dict[key]['chengji']=='300':
        print(key)
        a_dict.pop(key)

print('删除字典中value=300的新字典',a_dict)