On Mon, Sep 25, 2017 at 10:46 AM, Stefan Ram <r...@zedat.fu-berlin.de> wrote: > Chris Angelico <ros...@gmail.com> writes: >>On Mon, Sep 25, 2017 at 10:03 AM, Stefan Ram <r...@zedat.fu-berlin.de> wrote: >>>What's the difference between »builtins« and »_sitebuiltins«? >>>|>>> type.__module__ >>>|'builtins' >>>| >>>|>>> help.__module__ >>>|'_sitebuiltins' >>def sethelper(): >> builtins.help = _sitebuiltins._Helper() > > Thank you! > > I still have a related question. > > When I say, > > from math import floor > help() > > , Python will try to understand »help« and search for it in > the current scope. It will find a »help« there, as if after > > from builtins import * > > . Has it somewhere retained the information that »help« came > from »builtins«, so that one can write a function (or some > similar means) as follows: > > wherefrom( 'help' ) > > will return > > builtins > > or > > wherefrom( 'floor' ) > > will return > > math > > ?
Yes and no. You can't find out where you actually got something, because that 'something' is the same thing whereever you got it; but you CAN find the "canonical source" of something. Examples: >>> math.__name__ 'math' >>> import os >>> os.__name__ 'os' So far, so good. >>> import curses.ascii >>> curses.ascii.__name__ 'curses.ascii' Works for package modules too. Great! >>> import os.path >>> os.path.__name__ 'posixpath' Ah. Because 'os.path' actually comes from somewhere else. And it's the same module as if I said: >>> import posixpath >>> posixpath.__name__ 'posixpath' >>> os.path is posixpath True The same applies to functions. >>> from math import floor >>> floor.__module__ 'math' And classes. >>> from enum import Enum >>> Enum.__module__ 'enum' But if anything got imported from somewhere else, you get the _original_ source, not the one you got it from: >>> from ssl import namedtuple >>> namedtuple.__module__ 'collections' Is that good enough for what you need? It's not "where did this come from", but it's "where does this live". ChrisA -- https://mail.python.org/mailman/listinfo/python-list
