snow17.py (commit #55) syntax error

Your snow17.py script (line 263) has the following conditional expression that generates a syntax error:

ait((qw + w_q) <= ((deficit * (1 + plwhc)) + w_qx))):

Removing 'ait' fixes the syntax error. However, it seems this line should also be checked for correctness (even once 'ait' is removed).