Question

I want something like sys.builtin_module_names except for the standard library. Other things that didn’t work:

• sys.modules – only shows modules that have already been loaded
• sys.prefix – a path that would include non-standard library modules and doesn’t seem to work inside a virtualenv.

The reason I want this list is so that I can pass it to the --ignore-module or --ignore-dir command line options of trace.

So ultimately, I want to know how to ignore all the standard library modules when using trace or sys.settrace.

Answer 1

Why not work out what’s part of the standard library yourself?

import distutils.sysconfig as sysconfig
import os
std_lib = sysconfig.get_python_lib(standard_lib=True)
for top, dirs, files in os.walk(std_lib):
    for nm in files:
        if nm != '__init__.py' and nm[-3:] == '.py':
            print os.path.join(top, nm)[len(std_lib)+1:-3].replace(os.sep, '.')

gives

abc
aifc
antigravity
--- a bunch of other files ----
xml.parsers.expat
xml.sax.expatreader
xml.sax.handler
xml.sax.saxutils
xml.sax.xmlreader
xml.sax._exceptions

Edit: You’ll probably want to add a check to avoid site-packages if you need to avoid non-standard library modules.