python处理数据库append和extend的核心区别

c = []
a = ['11','2','33']
b = ['aa','b','cc']
c.append(a)
c.append(b)
print(c)

输出的结果是：[['11', '2', '33'], ['aa', 'b', 'cc']]

c = []
a = ['11','2','33']
b = ['aa','b','cc']
c.extend(a)
c.extend(b)
print(c)

输出的结果是['11', '2', '33', 'aa', 'b', 'cc']