li = ['alex','wusir','ritian','barry','wenzhou']
print(len(li)) # 长度 5
li.append("seven")
print(li) # ['alex', 'wusir', 'ritian', 'barry', 'wenzhou', 'seven']
li.insert(1,'Tony')
print(li) # ['alex', 'Tony', 'wusir', 'ritian', 'barry', 'wenzhou', 'seven']
li[2] = "Kelly"
print(li) #['alex', 'Tony', 'Kelly', 'ritian', 'barry', 'wenzhou', 'seven']
l2 = [1,'a',3,4,'heart']
li.extend(l2)
print(li) # ['alex', 'Tony', 'Kelly', 'ritian', 'barry', 'wenzhou', 'seven', 1, 'a', 3, 4, 'heart']
s = 'qwert'
li.extend(s)
print(li) # ['alex', 'Tony', 'Kelly', 'ritian', 'barry', 'wenzhou', 'seven', 1, 'a', 3, 4, 'heart', 'q', 'w', 'e', 'r', 't']
li.pop(li.index("ritian"))
print(li) # ['alex', 'Tony', 'Kelly', 'barry', 'wenzhou', 'seven', 1, 'a', 3, 4, 'heart', 'q', 'w', 'e', 'r', 't']
li.pop(1)
print(li) # 'Tony', ['alex', 'Kelly', 'barry', 'wenzhou', 'seven', 1, 'a', 3, 4, 'heart', 'q', 'w', 'e', 'r', 't']
del li[1:4]
print(li) # ['alex', 'seven', 1, 'a', 3, 4, 'heart', 'q', 'w', 'e', 'r', 't']
