Allowed abbrev to accept the dictionary object (good for passing in shelves or PersistentDictionaries).

src/utils.py

@@ -86,8 +86,9 @@ def eachSubstring(s):
     for i in xrange(1, len(s)+1):
         yield s[:i]
 
-def abbrev(strings):
+def abbrev(strings, d=None):
     """Returns a dictionary mapping unambiguous abbreviations to full forms."""
+    if d is None:
         d = {}
     for s in strings:
         for abbreviation in eachSubstring(s):