python5.17
# extend,两个列表之间进行相连# list1 = ["hello"]
# list2 = ["xiaowang"]
# list3 = 10000
# list1.extend(list2)
# # list1.extend(list3) 'int' object is not iterable
# print(list1) ['hello', 'xiaowang']
# index()函数，查看列表中的索引
# list1 = ["hello","python",10000]
# print(list1.index("python"))
# remove ,移除列表元素
# 如果同样的元素右两种以上，删除只会删除最前面的元素
# list1 = ["hello","python",10000,10086,"dcs"]
# list1.remove(10000)
# print(list1)
# del 根据索引进行删除
# list1 = ["hello","python",10000,10086,"dcs"]
# del list1
# print(list1)
# del list1
# print(list1)name 'list1' is not defined
# sort函数进行排序 0-9>A-Z>a>z不会产生新的列表
# sort不传入参数reverse，默认升序（默认值reverse=False）
# reverse=True,默认降序
# list1 = ["hello","python",10000,10086,"dcs"]
# list1.sort()
# print(list1) not supported between instances of 'int' and 'str'
# list1 =
# # list1.sort()
# list1.sort(reverse=True)
# print(list1)
# sorted()函数也是用来排序，，排序后会产生一个新的列表
# list1 =
# list2 = sorted(list1)
# list2 = sorted(list1,reverse=True)
# print(list2)
# reverse.函数翻转列表
# list1 =
# list1.reverse()
# print(list1)
# print(list1[::-1])
# pop函数，删除列表中的元素
# list1 = ["hello","python",10000,10086,"dcs"]
# list1.pop()['hello', 'python', 10000, 10086]
# print(list1)
# print(list1.pop(4))
# 元组，tuple = （），创建后里面的元素不能被修改
# tuple1 = ("hello","dcs",)
# print(tuple1)
# print(type(tuple1))<class 'tuple'>
# 当元组中只有一个元素，在末尾加一个逗号
# tuple1= ("xiaowang",)
# print(tuple1)
# print(type(tuple1))<class 'tuple'>
# 元组中的索引取值
# tuple1 = ("hello","dcs",)
# print(tuple1)
# print(tuple1)
# # tuple1 = "python"#元组值不能被修改
# tuple1.insert(0,"python")#元组不能添加新的值
# print(tuple1)
# 间接修改元组的值
# tuple1 = (1,2,3,4,6,9)
# list1 = list(tuple1)
# list1 = 5
# tuple2 = tuple(list1)
# print(tuple2)
# tuple1 = ("hello","dcs",)
# tuple1 = "xian01" ('hello', 'dcs', )
# print(tuple1)
# 迭代取值
# for i in tuple1:
# print(i)
# 字典
# dict1 = {"name":"xiaowang","age":10}
# print(dict1)
# print(type(dict1))<class 'dict'>
# list1 = [("name","xiaowang"),("age",19)]
# dict1 = dict(list1)
# print(dict1){'name': 'xiaowang', 'age': 19}
# 给字典添加键对值
# dict1 = {"name":"xiaowang","age":10}
# # dict1["age"] = 19
# # print(dict1)
# dict1["sex"] = "man"
# print(dict1){'name': 'xiaowang', 'age': 10, 'sex': 'man'}
# 取出字典里的键
# dict1 = {"name":"xiaowang","age":10}
# for i in dict1:
# print(i)
# 取字典里面的值
# dict1 = {"name":"xiaowang","age":10}
# for i in dict1.values():
# print(i)
# 针对性取值，根据键取值
# dict1 = {"name":"xiaowang","age":10}
# print(dict1["age"])
#添加字典
# dict1 = {"name":"xiaowang","age":10}
# # dict1.setdefault("sex","man")# {'name': 'xiaowang', 'age': 10, 'sex': 'man'}
# dict1.setdefault("sex")# {'name': 'xiaowang', 'age': 10, 'sex': None}
# print(dict1)
#删除字典
# dict1 = {"name":"xiaowang","age":10}
# #del dict1["age"]# {'name': 'xiaowang'}
# #del dict1 name 'dict1' is not defined
# dict1.clear(){}
# print(dict1)
#同时取键和值
# dict1 = {"name":"xiaowang","age":10,"sex":"man"}
# for i in dict1.keys():
# print(i,dict1)
# for k,v in dict1.items():
# print(k,v)
# pop函数，删除指定的键，并返回删除的值
# dict1 = {"name":"xiaowang","age":10,"sex":"man"}
# sex = dict1.pop("sex")
# print(dict1)
# print(sex)
# get函数,通过键来获取值
# dict1 = {"name":"xiaowang","age":10,"sex":"man"}
# print(dict1.get("sex"))
# fromkeys() ,定义一个初始化字典
# tuple1 = ("name","sex")
# dict1 = dict.fromkeys(tuple1)
# print(dict1)# {'name': None, 'sex': None}
# 指定值
# dict1 = dict.fromkeys(tuple1,"xiaowang")
# print(dict1){'name': 'xiaowang', 'sex': 'xiaowang'}
# 去重fromkeys(),基于键的唯一性，去重方式之一
# list1 =
# dict1 = dict.fromkeys(list1)
# list2 = list(dict1.keys())
# print(list2)
# __contains__函数，双划线表示私有函数，判断字典中是否含有某个值，返回布尔值
# dict1 = {"name":"xiaowang","age":10,"sex":"man"}
# print(dict1.__contains__("sex"))
# print(dict1.__contains__("user_name"))
# dict1 = {"name":"xiaowang","age":10,"sex":"man"}
# if dict1.__contains__("user_name"):
# print("判断正确")
# else:
# dict1.setdefault("user_name")
# print(dict1){'name': 'xiaowang', 'age': 10, 'sex': 'man', 'user_name': None}
# popitem函数返回并删除字典中的键对值一般删除末尾
# dict1 = {"name":"xiaowang","age":10,"sex":"man"}
# dict.popitem(dict1)
# print(dict1)
# update,利用一个字典更新另外一个字典
# dict1 = {"name":"xiaowang","age":10}
# dict2 = {"sex":"man"}
# dict1.update(dict2)
# print(dict1){'name': 'xiaowang', 'age': 10, 'sex': 'man'}
# 如果更新的元素在员字典中存在，把原来的值覆盖
# dict1 = {"name":"xiaowang","age":10,"sex":"man"}
# dict2 = {"age":23}
# dict1.update(dict2){'name': 'xiaowang', 'age': 23, 'sex': 'man'}
# print(dict1)
# 集合无序的
# 可变集合
# str1 = "xiaowang"
# set1 = set(str1)
# print(set1)
# set1.remove("w")
# print(set1)
# set1.clear()
# print(set1)
# print(set1.pop())
# set1.add("wang")
# print(set1)
# 不可变集合
# str1 = "xiaowang"
# set1 = frozenset(str1)
# set2 = set1.copy()
# print(set1)
# print(set2)
# 集合的去重
# list1 =
# set1 = set(list1)
# list2 = list(set1)
# print(list2)
# 集合的遍历
# str1 = "xiaowang"
# set1 = set(str1)
# for i in set1:
# print(i)
# list1 =
# list2 = []
# for i in set(list1):
# list2.append(i)
# print(list2)
# for i in list1:
# if i not in list2:
# list2.append(i)
# print(list2)
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