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

file:./
               state = STATIC
          created by   root:
            supplies   file:head_x.txt
            supplies   file:head_y.txt
            supplies   file:paste_x.txt
            supplies   file:plan.py
            supplies   file:tail_x.txt
            supplies   step:runpy ./plan.py
            supplies   step:runsh paste -d ' ' head_x.txt tail_x.txt > paste_x.txt

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

step:runpy ./plan.py
               state = SUCCEEDED
             env_var = STEPUP_PATH_FILTER [amended]
                 ngm = ['head_${*char}.txt', 'tail_${*char}.txt'] {'char': '?'}
           explained = yes
          created by   root:
            consumes   file:./
            consumes   file:plan.py
             creates   file:head_x.txt
             creates   file:head_y.txt
             creates   file:tail_x.txt
             creates   step:runsh paste -d ' ' head_x.txt tail_x.txt > paste_x.txt

file:head_x.txt
               state = STATIC
          created by   step:runpy ./plan.py
            consumes   file:./
            supplies   step:runsh paste -d ' ' head_x.txt tail_x.txt > paste_x.txt

file:head_y.txt
               state = STATIC
          created by   step:runpy ./plan.py
            consumes   file:./

file:tail_x.txt
               state = STATIC
          created by   step:runpy ./plan.py
            consumes   file:./
            supplies   step:runsh paste -d ' ' head_x.txt tail_x.txt > paste_x.txt

step:runsh paste -d ' ' head_x.txt tail_x.txt > paste_x.txt
               state = SUCCEEDED
           explained = yes
          created by   step:runpy ./plan.py
            consumes   file:./
            consumes   file:head_x.txt
            consumes   file:tail_x.txt
             creates   file:paste_x.txt
            supplies   file:paste_x.txt

file:paste_x.txt
               state = BUILT
          created by   step:runsh paste -d ' ' head_x.txt tail_x.txt > paste_x.txt
            consumes   file:./
            consumes   step:runsh paste -d ' ' head_x.txt tail_x.txt > paste_x.txt
