Explanation of list reference

[Rustom Mody]

On Saturday, February 15, 2014 7:14:39 PM UTC+5:30, Marko Rauhamaa wrote:
> Mark Lawrence:

> > I have no interest in understanding object identity, I can write code
> > quite happily without it.

> Luckily, what we are now debating is mostly terminology and points of
> view where the outcomes are unaffected.

> However, as an example, it is important to know if you should write:

>    if x is not None:
>        ...

> or if

>    if x != None:
>        ...

> is more robust.

Yes This is my main beef: 
Not that both are possible but that the first is *recommended* and the second not.

Something like a C compiler manual advising:
   You can write x*8 but its better to drop out into asm and write
   shl $3, %eax