Completion candidates are pulled from every module in PYSMELLTAGS

[rohdef]

What steps will reproduce the problem?

1. Normal completion.

What is the expected output? What do you see instead?

When I complete a bare word using pysmell, it seems to complete from every
symbol in PYSMELLTAGS*.

eg. Typing "op" shows every single open() function from every module
in the Python stdlib, regardless of what's been imported.

Preferably it would only complete symbols from imported modules, and
ideally only explicit symbol imports (from X import Y) or imported modules
(import X).