typo

theano/gof/utils.py

@@ -128,7 +128,7 @@ def get_variable_trace_string(v):
             traceback.print_list(v.tag.trace, sio)
         else:
             # Print separate message for each element in the list of
-            # batcktraces
+            # backtraces
             for idx, subtr in enumerate(tr):
                 if len(tr) > 1:
                     print("trace %d" % idx, file=sio)