1.not in
>>> a=2
>>> a not in [2,3,4]
False
>>> a in [2,3,4]
2. c if a else b #这里注意,一定要有b,而且b不能为pass
>>> a=3 if 2>3 else 4
>>> a
4
>>> a=3 if 2<3 else 4
>>> a
3.[fun(a) for a in [...]]
>>> [a+1 for a in [2,3,4,5,6]]
[3, 4, 5, 6, 7]
4.a,b=b,a
>>> a=1
>>> b=2
>>> a,b=b,a
>>> a
2
>>> b
1
5.'内容'.join([string array])
>>> '.'.join[2,3,4,5,6]
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: 'builtin_function_or_method' object has no attribute '__getitem__'
>>> '.'.join([2,3,4,5,6])
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: sequence item 0: expected string, int found
>>> '.'.join(['2','3','4','5','6'])
'2.3.4.5.6'