Best practice for Python: assert command() == False [closed]

问题

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Closed 6 years ago.

I wonder what is better/best:

>>> def command():
...     return False
...
>>> assert command() == False
>>> assert command() is False
>>> assert not command()

Cheers, Markus

回答1:

The most pythonic is the third. It is equivalent to:

assert bool(command()) != False

回答2:

Coding conventions can be studied here: PEP 8 Style Guide for Python Code

There you will find:

Don't compare boolean values to True or False using ==

Yes:   if greeting:
No:    if greeting == True:
Worse: if greeting is True:

来源：https://stackoverflow.com/questions/14733883/best-practice-for-python-assert-command-false