__builtins__ confusion...

[Tim Peters]

[Allan Crooks]
> ...
> This seems such a strange thing to me, can anyone explain why the
> value of __builtins__ differs?

Yes, but I'm not going to <wink>.  The name of the module holding the
builtins is __builtin__ (no 's'!).  __builtins__ is an internal
implementation detail, and user code should never muck with it.  From the
Ref Man:

    When a global name is not found in the global namespace, it is
    searched in the built-in namespace (which is actually the global
    namespace of the module __builtin__).  The built-in namespace
    associated with the execution of a code block is actually found by
    looking up the name __builtins__ in its global namespace; this should
    be a dictionary or a module (in the latter case its dictionary is
    used).  Normally, the __builtins__ namespace is the dictionary of the
    built-in module __builtin__ (note: no `s'); if it isn't, restricted
    execution mode is in effect.

The real reason __builtins__ is bound to the __builtin__ module instead of
to __builtin__'s dict in interactive mode is so that the curious don't get
flooded with output when doing

>>> vars()

at the prompt.