Print the full traceback when execution fails.

lms/djangoapps/debug/views.py

 """Views for debugging and diagnostics"""
 
 import pprint
+import traceback
 
 from django.http import Http404
 from django.contrib.auth.decorators import login_required
@@ -12,6 +13,7 @@ from codejail.safe_exec import safe_exec
 @login_required
 @ensure_csrf_cookie
 def run_python(request):
+    """A page to allow testing the Python sandbox on a production server."""
     if not request.user.is_staff:
         raise Http404
     c = {}
@@ -23,7 +25,7 @@ def run_python(request):
         try:
             safe_exec(py_code, g)
         except Exception as e:
-            c['results'] = str(e)
+            c['results'] = traceback.format_exc()
         else:
             c['results'] = pprint.pformat(g)
     return render_to_response("debug/run_python_form.html", c)