列表：
list = ["apple","Banana","orange","grape"]
1、添加数据方法：
方法一：append（往列表的结尾处添加一个元素）
示例：
list = ["apple","Banana","orange","grape"]
list.append("mango")
print(list)
方法二：insert（往列表中指定索引位置插入元素）
示例：
list = ["apple","Banana","orange","grape"]
list.insert(0,"mango")
print(list)
特别注意：（插入数据如果用的是反向索引，会先转换为正向索引再进行数据插入）
示例：
list = ["apple","Banana","orange","grape"]
list.insert(-1,"mango")
print(list)
特别提示：（插入数据用的索引超出列表的索引范围，会默认插入到最后一个）
示例：
list = ["apple","Banana","orange","grape"]
list.insert(10,"mango")
print(list)
方法三：extend（一次性往列表尾部插入多个元素）
extend方法传列表：
示例：
list = ["apple","Banana","orange","grape"]
list.extend(["pitaya","mango"])
print(list)
extend方法传字符串：（会把字符串中的每一个字符当做一个元素插入到列表）
示例：
list = ["apple","Banana","orange","grape"]
list.extend("abcd")
print(list)
2、删除数据方法：
list = ["apple","Banana","orange","grape","pitaya","mango"]
方法一：remove：指定元素进行删除(若列表中存在多个相同的元素，只会删除找到的第一个元素)
示例：
list = ["apple","Banana","orange","grape","pitaya","mango","apple","Banana"]
list.remove("apple")
print(list)
方法二：pop：指定索引进行删除(如果不指定位置，默认删除列表最后一个元素)
示例：
list = ["apple","Banana","orange","grape","pitaya","mango","apple","Banana"]
list.pop()
print(list)
备注：pop方法调用完，会返回生产的数据。
示例：
list = ["apple","Banana","orange","grape","pitaya","mango","apple","Banana"]
list1 = list.pop(0)
print(list)
print(list1)
方法三：clear（清空列表中的所有元素）
示例：
list = ["apple","Banana","orange","grape","pitaya","mango","apple","Banana"]
list.clear()
print(list)
3、修改列表中元素的值：
通过索引字指定位置进行修改
示例：
list = ["apple","Banana","orange","grape"]
list[2] = "mango"
print(list)
4、查找列表中的元素：
索引取值：
示例：
list = ["apple","Banana","orange","grape"]
list1 = list[2]
print(list1)
查询列表中元素对应的索引：
方法一：index（查找的元素在列表中不存在时，会抛异常）
示例1：
list = ["apple","Banana","orange","grape"]
list1 = list.index("orange")
print(list1)
示例2：
list = ["apple","Banana","orange","grape"]
list1 = list.index("mango")
print(list1)
方法二：count统计列表中某一个元素的个数
示例：
list = ["apple","Banana","apple","orange","apple","grape","apple"]
res = list.count("apple")
print(res)
特别提示：如何识别使用方法后要不要用变量接收返回数据，按住【CTRL】键，鼠标光标移动到方法名上边，提示弹窗方法名后的>符号显示的是None，就不需要变量接收数据。