列表的引入：
a1 = "老王"
a2 = "老李"
a3 = "老刘"
#列表
names = ["老王","老李","老刘"] #定义了一个列表
nums = [11,22,3.14,"100","laowang","老李"] #可以存储不同类型的数据
列表的增删改查：
append添加到原有列表的最后
names.append("老赵") # ["老王","老李","老刘","老赵"]
names.append("悟空") # ["老王","老李","老刘","老赵","悟空"]
insert
name.insert(位置，要添加的内容）
names.insert(0,"八戒") # ["八戒","老王","老李","老刘","老赵","悟空"]
names.insert(2,"沙僧") # ["八戒","老王","沙僧","老李","老刘","老赵","悟空"]
names2 = ["葫芦娃","叮当猫","猴子"]
合并两个列表:
name3 = names + names2 # ["八戒","老王","沙僧","老李","老刘","老赵","悟空","葫芦娃","叮当猫","猴子"]
names.extend(names3) #压栈 ["八戒","老王","沙僧","老李","老刘","老赵","悟空","八戒","老王","沙僧"，"老李","老刘","老赵","悟空","葫芦娃","叮当猫","猴子"]
names.pop() #弹栈 返回"猴子" 列表剩余：["八戒","老王","沙僧","老李","老刘","老赵","悟空","八戒","老王","沙僧"，"老李","老刘","老赵","悟空","葫芦娃","叮当猫"]
注意：
li = [23,24,25,26]
li1 = [31,32]
区别：
li.extend(li1) # [23, 24, 25, 26, 31, 32]
li.append(li1) # [23, 24, 25, 26, [31, 32]]
names.remove("老王") #根据内容删除，只删除一次 列表剩余：["八戒","沙僧","老李","老刘","老赵","悟空","八戒","老王","沙僧","老李","老刘","老赵","悟空","葫芦娃","叮当猫"]
names[0] names[1] names[2]
names[2:5] # ["老李","老刘","老赵"]
del names[0] # 删除"八戒" ["沙僧","老李","老刘","老赵","悟空","八戒","老王","沙僧","老李","老刘","老赵","悟空","葫芦娃","叮当猫"]
总结：
添加新元素：
append()
insert()
extend()
删除元素：
pop() ->删除最后一个
remove() ->根据内容删除
del xxx[下标] ->根据下标来删除
查询：in not in
name[0] = "沙师弟" # 改 ["沙师弟","老李","老刘","老赵","悟空","八戒","老王","沙僧","老李","老刘","老赵","悟空","葫芦娃","叮当猫"]
if "老赵" in names:
print("找到了...")
if "老赵" not in "names":
print("可以添加老赵")
