TypeError: ' Nonetype ' object has no attribute ' __getitem__ '

Buildbot version: (0.8.10)

Bug:typeerror: ' Nonetype ' object has no attribute ' __getitem__ '

Reference page: http://trac.buildbot.net/ticket/3107?cversion=0&cnum_hist=3

The code for modifying the error section in file slaves.py is

1         Try : 2             max_builds = Int (request.args.get ('numbuilds', ['ten' ) ]) [0])3         except  (TypeError, valueerror):4             max_ Builds = 10

TypeError: ' Nonetype ' object has no attribute ' __getitem__ '