root:
             product   file:plan.py
             product   step:./plan.py

file:plan.py
               state = CONFIRMED
             creator   root:
                sink   step:./plan.py

step:./plan.py
               state = SUCCEEDED
                need = PLAN
           using_env = STEPUP_PATH_FILTER [dynamic]
             creator   root:
              source   file:plan.py
             product   step:echo A; mv s.free s.used; mv t1.free t1.used; sleep 1; mv s.used s.free; mv t1.used t1.free
             product   step:echo B; mv t2.free t2.used; sleep 1; mv t2.used t2.free
             product   step:echo C; mv s.free s.used; sleep 1; mv s.used s.free

step:echo A; mv s.free s.used; mv t1.free t1.used; sleep 1; mv s.used s.free; mv t1.used t1.free
               state = SUCCEEDED
                need = DEFAULT
            resource = slot: 1 units
            resource = token: 1 units
             creator   step:./plan.py

step:echo B; mv t2.free t2.used; sleep 1; mv t2.used t2.free
               state = SUCCEEDED
                need = DEFAULT
            resource = token: 1 units
             creator   step:./plan.py

step:echo C; mv s.free s.used; sleep 1; mv s.used s.free
               state = SUCCEEDED
                need = DEFAULT
            resource = slot: 1 units
             creator   step:./plan.py
