[Pywikipedia-l] recognizing a leading space in replace.py

I'm trying to run this command:

python replace.py -regex " (from wikipedia)}}" "}}" -file:sfwn1e -log:sfwlog -summary:"adding argument to {{from wikipedia raw}} template - Step 2 of 2, change local pagename to Wikipedia pagename"

But I get the output:

No changes were necessary in [[Oral rehydration therapy (from Wikipedia)]]

for every file, even though this text is present in every file: (from wikipedia)}}

...including the leading space.

Do I need to use a special character to insert the space? (And regex?) I tried %20 instead of the space but it didn't work.

Thanks