Jul 23, 2021 · The not key word inverts a boolean (true or false value), turning True into False. What this means is that if you want a piece of code to run if a variable is false than by using not you can make that run. Example to help: finished_game = False while not finished_game:#While the game isn't finished #run game code Does that make sense?

Use the keyword and, not & because & is a bit operator. Be careful with this... just so you know, in Java and C++, the & operator is ALSO a bit operator. The correct way to do a boolean comparison in those languages is &&. Similarly | is a bit operator, and || is a boolean operator. In Python and and or are used for boolean comparisons.

Python checks whether the object you're referring to has the same memory address as the global None object - a very, very fast comparison of two numbers. By comparing equality, Python has to look up whether your object has an __eq__ method. If it does not, it examines each superclass looking for an __eq__ method. If it finds one, Python calls it.

Jun 16, 2012 · There are two operators in Python for the "not equal" condition - a.) != If values of the two operands are not equal, then the condition becomes true. (a != b) is true. b.) <> If values of the two operands are not equal, then the condition becomes true. (a <> b) is true. This is similar to the != operator.

Nov 6, 2015 · (not A) and (not B) is equivalent to not (A or B), and (not A) or (not B) is equivalent to not (A and B). Technically, it's very slightly faster to use the latter, e.g. not (A and B), as the interpreter evaluates fewer logical statements, but it's trivial. Use the logical structure that allows you to state the condition as clearly as possible ...

TLDR: The bytecode compiler parses them both to x is not None - so for readability's sake, use if x is not None. Readability. We use Python because we value things like human readability, useability, and correctness of various paradigms of programming over performance. Python optimizes for readability, especially in this context.

So OP's rule never mentions what to do IF tuple not in list. Apart from that, as the other answers have noted, not in is the correct syntax to check if an object is in a list (or any container really). For example: # check if `my_tuple` is not in `my_list` my_tuple not in my_list

May 24, 2013 · Yes, if bar is not None is more explicit, and thus better, assuming it is indeed what you want. That's not always the case, there are subtle differences: if not bar: will execute if bar is any kind of zero or empty container, or False. Many people do use not bar where they really do mean bar is not None.

Aug 13, 2017 · It's not a statement, it's an expression (three expressions*, really). If you remove the and not found part, the search will not stop when it finds the item, it will keep going until it reaches the end. With the and not found, it stops when it finds the item.

Aug 17, 2017 · And don't confuse Python's for with a C for loop; Python's is a For Each construct. As such it doesn't 'produce' an iterable, it requires an iterable as input. The other is a membership test operation, and operators are a type of expression: The operators in and not in test for membership. It is meant to apply to containers (not just iterables).