字典操作

 dic = {
     'name':['大猛','小孟'],
     'py9':[{'num':71,'avg_age':18,},
            {'num': 71, 'avg_age': 18, },
            {'num': 71, 'avg_age': 18, },
            ],
     True:1,
     (1,2,3):'wuyiyi',
     2:'二哥',
 }
 print(dic)
dic1 = {'age': 18, 'name': 'jin', 'sex': 'male',}
#增：
 dic1['high'] = 185  #没有键值对，添加
 dic1['age'] = 16  #如果有键，则值覆盖

 dic1.setdefault('weight')  # 有键值对，不做任何改变，没有才添加。
 dic1.setdefault('weight',150)
 dic1.setdefault('name','二哥')
 print(dic1)

#删
 print(dic1.pop('age'))   # 有返回值，按键去删除
 print(dic1.pop('二哥',None))   # 可设置返回值
 print(dic1)

 print(dic1.popitem())  # 随机删除 有返回值 元组里面是删除的键值。
 # print(dic1)

 del dic1['name1']
 print(dic1)
 del dic1
 print(dic1)

 dic1.clear() #清空字典

#改  update
 dic1['age'] = 16

 dic = {"name":"jin","age":18,"sex":"male"}
 dic2 = {"name":"alex","weight":75}
 dic2.update(dic)  #
#
 print(dic)
 print(dic2)
dic1 = {'age': 18, 'name': 'jin', 'sex': 'male',}
#查
 print(dic1.keys(),type(dic1.keys()))
 print(dic1.values())
 print(dic1.items())

 for i in dic1:
     print(i)
 for i in dic1.keys():
     print(i)

 for i in dic1.values():
     print(i)

 a,b = 1,2
 print(a,b)

 a = 1
 b = 2
 a,b = b,a
 print(a,b)
 a,b = [1,2],[2,3]
 a,b = (1,2)
 print(a,b)

 for k,v in dic1.items():
     print(k,v)

 v1 = dic1['name']
 print(v1)

 v2 = dic1['name1']  # 报错
 print(v2)

 print(dic1.get('name1','没有这个键'))