[recipes.py] use argparse to set command automatically.

recipe_engine/depgraph.py

 # Copyright 2016 The LUCI Authors. All rights reserved.
 # Use of this source code is governed under the Apache License, Version 2.0
 # that can be found in the LICENSE file.
 
 from __future__ import print_function
 
 import sys
 
 from . import loader
 
@@ skipping 30 matching lines @@
       'Ignore a recipe package (e.g. recipe_engine). Can be passed '
       'multiple times'))
   depgraph_p.add_argument(
     '--recipe-filter', default='',
     help=(
       'A recipe substring to examine. If present, the depgraph will '
       'include a recipe section containing recipes whose names contain '
       'this substring. It will also filter all nodes of the graph to only '
       'include modules touched by the filtered recipes.'))
 
-  depgraph_p.set_defaults(command='depgraph', func=main)
+  depgraph_p.set_defaults(func=main)
 
 
 def main(package_deps, args):
   universe = loader.RecipeUniverse(package_deps, args.package)
   own_package = package_deps.root_package
 
   module_to_package = {}
 
   # All deps maps a tuple of (is_recipe, id) to deps (list of ids). is_recipe is
   # a boolean, all ids are strings.
@@ skipping 80 matching lines @@
     print('  subgraph "cluster_%s" { label="%s"; %s; }' % (
         package, package, '; '.join(modules)), file=args.output)
 
   if args.recipe_filter and recipe_to_package:
     recipe_names = [
         '"recipe %s"' % name for name in recipe_to_package.keys()]
     print('  subgraph "cluster_recipes" { label="recipes"; %s; }' % (
         '; '.join(recipe_names)), file=args.output)
 
   print(_GRAPH_FOOTER, file=args.output)