Tricky Areas in Python

[Peter Hansen]

Tim Roberts wrote:
> "PyPK" <superprad at gmail.com> wrote:
>>What possible tricky areas/questions could be asked in Python based
>>Technical Interviews?
> 
> What's the point of asking "tricky" questions?  Aren't you really more
> interested in what applications they have worked on and whether they were
> successful?
> 
> I don't know.  I'm not sure I need a job with a company that insists on
> playing "Programming Jeopardy" during the interview.

That's okay.  Those companies don't need you either. ;-)

Seriously though, the point of asking such questions is that with 
minimal effort they _can_ (not "definitely will") quickly qualify a 
candidate's level of expertise in a language.  Novices, and those who 
while they might have programmed in a language for several years still 
don't really understand it deeply enough to be considered entirely safe 
on their own, will generally trip up on all or most such questions 
(where "trip up" means anything from giving wrong answers to giving you 
the "deer in the headlights" look).  _Anyone_ could trip up on one or 
two of them, especially given the pressure of an interview situation. 
(And even seeing an expert trip up under pressure tells you something 
useful about the candidate.)

In short, a true senior programmer will provide good correct answers to 
most such questions, while those less senior generally will not.

Asking such questions in isolation, without also delving deeply into 
other background such as what applications you've worked on, is just as 
dangerous as asking _only_ about such applications.  I've made the 
mistake of hiring people who had lengthy involvement -- apparently at a 
senior level -- in significant projects, only to discover that they 
clearly didn't understand some basic concepts of the languages 
supposedly used.  My conclusion was that they were in that class of 
people who manage to interview well yet contribute little, but have 
lucked out repeatedly by working for companies who were incompetent at 
terminating for cause (and there are _many_ such companies).  (We didn't 
make the same mistake and fired them reasonably quickly.)

-Peter