classmates = ['Michael', 'Bob', 'Tracy']
# print(classmates[0])
# print(len(classmates))
# print(classmates[-1])
# print(classmates[len(classmates) - 1])
# 添加删除元素
classmates.append('hehe');
print(classmates)
classmates.insert(0, 'haha');
print(classmates)
classmates.pop()
print(classmates)
classmates.pop(0);
print(classmates)
