root:
             version = v1
             creates   file:./
             creates   file:plan.py
             creates   step:./plan.py

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

file:./
                path = ./
               state = STATIC
          created by   root:
            supplies   file:foo.txt
            supplies   file:plan.py
            supplies   step:./plan.py
            supplies   step:cat foo.txt

step:./plan.py
             workdir = ./
             command = ./plan.py
               state = RUNNING
          created by   root:
            consumes   file:./
            consumes   file:plan.py
             creates   dg:'*.txt'
             creates   step:cat foo.txt

dg:'*.txt'
          created by   step:./plan.py
             creates   file:foo.txt

file:foo.txt
                path = foo.txt
               state = STATIC
          created by   dg:'*.txt'
            consumes   file:./
            supplies   step:cat foo.txt

step:cat foo.txt
             workdir = ./
             command = cat foo.txt
               state = QUEUED
          created by   step:./plan.py
            consumes   file:./
            consumes   file:foo.txt
