I do a lot of urllib2 reads of HTTP URLs.  From time to time, I see the
following exception being thrown:

  File "/usr/local/lib/python2.5/socket.py", line 291, in read
    data = self._sock.recv(recv_size)
  File "/usr/local/lib/python2.5/httplib.py", line 509, in read
    return self._read_chunked(amt)
  File "/usr/local/lib/python2.5/httplib.py", line 548, in _read_chunked
    chunk_left = int(line, 16)
ValueError: invalid literal for int() with base 16: ''

The chunked reading code does not expect an empty string.  I have
attached a patch which checks for ValueError in this case and sets
chunk_left to 0, which will break from the loop.  I am not entirely sure
if this is the correct fix, however, but it should illustrate the problem.