message: Fix for python < 3.5.
diff: @@ -51,8 +51,8 @@ class Boost(drake.Configuration):
  'coroutine': 'coroutine',
  'iostreams': 'iostreams',
  'python': list(itertools.chain(
  - *(('python3{}'.format(v), 'python-3.{}'.format(v)) for v in range(7)),
  - ['python3', 'python']))
  + *(('python3{}'.format(v), 'python-3.{}'.format(v)) for v in range(7)))) \
  + + ['python3', 'python']
  }
  def __init__(self,
  