root:
             creates   file:./
             creates   file:plan.py
             creates   step:runpy ./plan.py

file:./
               state = STATIC
          created by   root:
            supplies   file:README.txt
            supplies   file:inventory.txt
            supplies   file:plan.py
            supplies   step:make-inventory README.txt -o inventory.txt
            supplies   step:runpy ./plan.py

file:plan.py
               state = STATIC
          created by   root:
            consumes   file:./
            supplies   step:runpy ./plan.py

step:runpy ./plan.py
               state = SUCCEEDED
          created by   root:
            consumes   file:./
            consumes   file:plan.py
             creates   file:README.txt
             creates   step:make-inventory README.txt -o inventory.txt

file:README.txt
               state = STATIC
          created by   step:runpy ./plan.py
            consumes   file:./
            supplies   step:make-inventory README.txt -o inventory.txt

step:make-inventory README.txt -o inventory.txt
               state = SUCCEEDED
          created by   step:runpy ./plan.py
            consumes   file:./
            consumes   file:README.txt
             creates   file:inventory.txt
            supplies   file:inventory.txt

file:inventory.txt
               state = BUILT
          created by   step:make-inventory README.txt -o inventory.txt
            consumes   file:./
            consumes   step:make-inventory README.txt -o inventory.txt
