Import a module.
The 'globals' argument is used to infer where the import is occurring from
to handle relative imports. The 'locals' argument is ignored. The
'fromlist' argument specifies what should exist as attributes on the module
being imported (e.g. ``from module import <fromlist>``). The 'level'
argument represents the package location to import from in a relative
import (e.g. ``from ..pkg import mod`` would have a 'level' of 2).