__instancecheck__ metaclasses, how do they work: why do I get True when I tuple, why doesn't print run?

[Rhodri James]

On 04/11/2019 22:23, Peter J. Holzer wrote:
> On 2019-11-04 14:54:23 +0000, Rhodri James wrote:
>> On 04/11/2019 14:33, Veek M wrote:
>>> __metaclass__ = whatever; # is python2.x syntax
>>
>> But not Python3: see PEP 3115
> 
> Doesn't "X is python2.x syntax" imply "X is not python3 syntax"?

Not necessarily, the OP might have (and apparently was) assuming that it 
was also Python3 syntax.  Also it gave me an opportunity to point him to 
the appropriate PEP.  That said, we've reached the limits of my 
knowledge here and I'm bowing out of the discussion.

-- 
Rhodri James *-* Kynesim Ltd