issue2550850 anypy/email_.py uses BSPACE which is not defined in python 2.7

Supplied a definition for BSPACE since it seems to not be defined
anywhere (even searching a python 3.4 install didn't turn up a definition for
it). BSPACE definition taken from:

  http://svn.python.org/projects/python/branches/py3k-urllib/Lib/email/header.py

which is almost identical code. Put definition of BSPACE just before
the reference to minimize scope and chance of unintended issues. This
isn't the best place because it will be redefined every time through,
but this is not a heavily used code path or it would have been
found/fixed long ago.

Author: rouilj

CHANGES.txt

@@ -123,6 +123,9 @@ Fixed:
   pagesize is not propigated to the prev link. This patch fixes that.
   Patch provided by John Kristensen. (Applied, light testing by John
   Rouillard.)
+- issue2550850 anypy/email_.py uses BSPACE which is not defined in python 2.7
+  Supplied a definition for BSPACE since it seems to not be defined
+  anywhere. Reported by Dennis Boone. (John Rouillard)
 
 2016-01-11: 1.5.1
 

roundup/anypy/email_.py

@@ -122,6 +122,7 @@ def decode_header(header):
             last_word = word
             last_charset = charset
         elif last_charset is None:
+            BSPACE = b' '
             last_word += BSPACE + word
         else:
             last_word += word