Is De Morgan's Law Pythonic?

Question

Which of the following if statements is more Pythonic?

if not a and not b:     do_something 

OR

if not ( a or b ):     do something 

Its not predicate logic so I should use the Python key words because its more readable right?

In the later solution more optimal than the other? (I don't believe so.)

Is there any PEP-8 guides on this?

Byte code of the two approaches(if it matters):

In [43]: def func1():     if not a and not b:         return    ....:         ....:       In [46]: def func2():     if not(a or b):         return    ....:         ....:       In [49]: dis.dis(func1)   2           0 LOAD_GLOBAL              0 (a)               3 UNARY_NOT                          4 JUMP_IF_FALSE           13 (to 20)               7 POP_TOP                            8 LOAD_GLOBAL              1 (b)              11 UNARY_NOT                         12 JUMP_IF_FALSE            5 (to 20)              15 POP_TOP                 3          16 LOAD_CONST               0 (None)              19 RETURN_VALUE                 >>   20 POP_TOP                           21 LOAD_CONST               0 (None)              24 RETURN_VALUE          In [50]: dis.dis(func2)   2           0 LOAD_GLOBAL              0 (a)               3 JUMP_IF_TRUE             4 (to 10)               6 POP_TOP                            7 LOAD_GLOBAL              1 (b)         >>   10 JUMP_IF_TRUE             5 (to 18)              13 POP_TOP                 3          14 LOAD_CONST               0 (None)              17 RETURN_VALUE                 >>   18 POP_TOP                           19 LOAD_CONST               0 (None)              22 RETURN_VALUE         

Answer 1

I'd say whichever is easier for you to read, depending on what a and b are.

Answer 2

I think both your examples are equally readable, however if I wanted to "push the boat out" on readability I would go with:

not any((a, b)) 

Since to me this reads much more like English, and hence is the most Pythonic.