big_yx, little_yx = self.source_yxyx(yx)
if big_yx in obstacles and little_yx in obstacles[big_yx]:
self.source_map_segment += 'X'
big_yx, little_yx = self.source_yxyx(yx)
if big_yx in obstacles and little_yx in obstacles[big_yx]:
self.source_map_segment += 'X'