dict = {"k1": "v1", "k2": "v2", "k3": "v3"}
# dict["k4"]="v4"
# # dict["k2"]="v2"
# print(dict)
# dict.setdefault("k2", "v2")
# dict.setdefault("k4","v4")
# print(dict)
# 删
# dict = {"k1": "v1", "k2": "v2", "k3": "v3"}
# re=dict.pop('k2')
# print(re)
# print(dict)
# k,v=dict.popitem()
# print(k,v)
# print(dict)
# print(k)
# dict.clear()
# print(dict)
# del dict
# print(dict)删除列表，列表不存在
# dict = {"k1": "v1", "k2": "v2", "k3": "v3"}
# # dict1={"k": "v","k4": "v3"}
# # dict.update(dict1)
# # print(dict)
# # {'k1': 'v1', 'k2': 'v2', 'k3': 'v3', 'k': 'v', 'k4': 'v3'}
# dict.update([("k1", "v1")])
# print(dict)
dict = {"k1": "v1", "k2": "v2", "k3": "v3"}
# dict.update(k1= "v4")
# print(dict)
# 查
# dict = {"k1": "v1", "k2": "v2", "k3": "v3"}
# re=dict.get("k2")
# print(re)
# re=dict.keys()
# print(re)
# for i in re:
# print(i)
# re=dict.values()
# print(re)
# print(type(re))
# for v,k in dict.items():
# print(v,k,sep=' ')
# print(k)