Improve our error messages for non compatibility.

Carreau · Carreau · commit 4cb6b8a95098 · 2016-08-23T11:15:06.000-07:00
diff --git a/IPython/__init__.py b/IPython/__init__.py
@@ -29,10 +29,10 @@
 #-----------------------------------------------------------------------------
 
 # Don't forget to also update setup.py when this changes!
-v = sys.version_info
-if v[:2] < (3,3):
-    raise ImportError('IPython requires Python version 3.3 or above.')
-del v
+if sys.version_info < (3,3):
+    raise ImportError('IPython 6.0+ requires Python version 3.3 or above. '
+                      'For a version compatible with Python 2.7, please install'
+                      ' the 5.x Long Term Support version.')
 
 # Make it easy to import extensions - they are always directly on pythonpath.
 # Therefore, non-IPython modules can be added to extensions directory.
@@ -143,4 +143,3 @@ def start_kernel(argv=None, **kwargs):
     """
     from IPython.kernel.zmq.kernelapp import launch_new_instance
     return launch_new_instance(argv=argv, **kwargs)
-    
