Patch #411055 from MvL: import each extension after building it, and     delete ones that can't be imported due to missing symbols or other     causes.
Patch #411055 from MvL: import each extension after building it, and
    delete ones that can't be imported due to missing symbols or other
    causes.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator