const-param images.py:1 compose_strips
  calls: 2 prod, 0 test
  gap: default 0 never overridden
  margin: default 0 never overridden
  border: default 0 never overridden
  strict: default True never overridden, passed explicitly at 1 site
  suggest: drop gap, margin, border, use 0 inline; drop strict (and the argument at images.py:12), use True inline
