use try/except also for Py2.

imp.reload is actually aliased to the builtin

IPython/core/extensions.py

@@ -11,13 +11,12 b' import sys'
 from traitlets.config.configurable import Configurable
 from IPython.utils.path import ensure_dir_exists
 from traitlets import Instance
-from IPython.utils.py3compat import PY3
-if PY3:
-    try: 
-        from importlib import reload
-    except ImportError :
-        ## deprecated since 3.4
-        from imp import reload
+
+try:
+    from importlib import reload
+except ImportError :
+    ## deprecated since 3.4
+    from imp import reload
 
 #-----------------------------------------------------------------------------
 # Main class