print(do_nothing()) # None def do_nothing(): pass print(do_nothing()) if do_nothing(): #do_nothing() 返回None 布尔值为false所以不会运行到print,返回None print('...') print(do_nothing()) if not do_nothing(): #do_nothing() 返回None not do_nothing布尔值为T,所以会运行到print,返...
1、空语句 do nothing 2、保证格式完整 3、保证语义完整 4、以if语句为例: C/C++中写法: if(true) ; // do nothing else {} // do nothing python中写法: if true: pass # do nothing else: print "do something." yield #??? http://www.cnblogs.com/tqsummer/archive/2010/12/27/1917927.htm...
return Counter(first_string) == Counter(second_string) print(check_if_anagram('testinG', 'Testing')) # True print(check_if_anagram('Here', 'Rehe')) # True print(check_if_anagram('Know', 'Now')) # False 可以使用sorted()方法。 def check_if_anagram(first_word, second_word): first_...
作用: (1)空语句:do nothing (2)保证格式完整 (3)保证语义完整 if true: pass # do nothing def iplaypython(): pass # 保证格式完整 while True: pass # 保证语义完整 1. 2. 3. 4. 5. 6. 7. 8.
>>> if thing is None: # 为了区分 None 和 False 的区别,这里使用 is ... print("It's nothing") ... else: ... print("It's something") ... It's nothing >>> 1. 2. 3. 4. 5. 6. 7. 8. 这看起来是一个微妙的差别,但对于Python 来说是很重要的。
If the element is not a member, do nothing. 移除指定元素,不存在不保错 """ pass def intersection(self, *args, **kwargs): # real signature unknown """ Return the intersection of two sets as a new set. 交集 (i.e. all elements that are in both sets.) """ pass def intersection_...
# executed onlyifthe loop didn't"break".pass # Do nothingifrangelist[1]==2: print"The second item (lists are 0-based) is 2"elif rangelist[1]==3: print"The second item (lists are 0-based) is 3"else: print"Dunno"whilerangelist[1]==1: ...
Sometimes, it’s useful to pass arguments to your decorators. For instance, @do_twice could be extended to a @repeat(num_times) decorator. The number of times to execute the decorated function could then be given as an argument.If you define @repeat, you could do something like this:...
Common Mistake #10: Misusing the__del__method Let’s say you had this in a file calledmod.py: import fooclassBar(object): ...def__del__(self): foo.cleanup(self.myhandle) And you then tried to do this fromanother_mod.py:
How do you check if you have pip?Show/Hide How can you install packages from a requirements.txt with pip?Show/Hide Get Your Cheat Sheet: Click here to download a free pip cheat sheet that summarizes the most important pip commands. Take the Quiz: Test your knowledge with our interactiv...