remove unnecessary loop to import manualy modules in `completer lib`

IPython/core/completerlib.py

@@ -159,9 +159,6 b' def try_import(mod, only_modules=False):'
         m = import_module(mod)
     except:
         return []
-    mods = mod.split('.')
-    for module in mods[1:]:
-        m = getattr(m, module)
 
     m_is_init = hasattr(m, '__file__') and '__init__' in m.__file__