Seige machine builds causes unknown failure

[skatterbrain]

If a seige machine is selected to be built, the bot fails with "some error". Debug
trace below pointed to building a seige machine. Deselecting seige machine fixes
error. Happens if seige machine is selected whether on th11 or 12


Clicking on buttons/army_overview_quicktrain ([[515, 90]])
Clicking at 781, 327...
Some Issue Occurred: , <type 'exceptions.AssertionError'>
Traceback (most recent call last):
  File "bot.py", line 186, in run
  File "maintainer.py", line 491, in train_and_maintain
  File "maintainer.py", line 425, in train_troops
  File "maintainer.py", line 400, in build_siegemachines
  File "player.py", line 136, in click_on
  File "player.py", line 264, in locate
  File "player.py", line 232, in load_image
AssertionError