anchor.diff:  
     mkPython =
       { name
  +    , dirname
       , version
       , src
       , python
  
positive.code:           # generate MANIFEST.in to make sure every file is included
            rm -f MANIFEST.in
            cat > MANIFEST.in <<EOF
            recursive-include ${name}/*
  
            include VERSION
            include ${name}/*.ini
            include ${name}/*.json
            include ${name}/*.mako
            include ${name}/*.yml
  
            recursive-exclude * __pycache__
            recursive-exclude * *.py[co]
  
negative.code:   mkBackend =
      args @
      { name
      , dirname
      , version
      , src
      , python
  