Python学习第五篇——如何访问字典

 # the example_1 aim to tell how to use dctionary,and how to access list or dictionary
 infos={"first_name":"jack","last_name":"mole","age":20,"city":"lendon"}
 for  info  in infos:
     print(str(infos[info]))
 # example2 aim to how to access dictionary's key and value
 friends_num = {"wang":8,"li":0,"jack":3,"mole":6,"zhao":5}
 for friend_num in friends_num:
     #print(friend_num)
     print("my friend "+friend_num+
         " like "+str(friends_num[friend_num]))
     

1 上述代码的作用在于介绍字典的概念：字典的核心概念在于：键——值，这样的对应关系，字典并不关心键和键的顺序关系，只关心键——值的对应关系

2 正确访问字典：字典名[键]——访问值，同时通过程序2中对键本身的访问，再次理解访问 列表或者字典时，for关键字后面的变量究竟意味着什么？？