fix pep8 issues with in PR 3057

theano/printing.py

@@ -954,12 +954,12 @@ def pydotprint(fct, outfile=None,
     else:
         try:
             g.write(outfile, prog='dot', format=format)
-        except pd.InvocationException as e:
+        except pd.InvocationException:
             # based on https://github.com/Theano/Theano/issues/2988
             if map(int, pd.__version__.split(".")) < [1, 0, 28]:
-                raise Exception("Old version of pydot detected, which can cause"
-                                " issues with pydot printing. Try upgrading "
-                                "pydot version to a newer one")
+                raise Exception("Old version of pydot detected, which can "
+                                "cause issues with pydot printing. Try "
+                                "upgrading pydot version to a newer one")
             raise
 
         if print_output_file: