docs: def registry_comparison(registry0, registry1):
      """Compares two dictionaries of registry keys returning their difference."""
      comparison = {'created_keys': {},
                    'deleted_keys': [],
                    'created_values': {},
                    'deleted_values': {},
                    'modified_values': {}}
  
      for key, info in registry1.items():
          if key in registry0:
              if info[1] != registry0[key][1]:
                  created, deleted, modified = compare_values(
                      registry0[key][1], info[1])
  
                  if created:
                      comparison['created_values'][key] = (info[0], created)
                  if deleted:
                      comparison['deleted_values'][key] = (info[0], deleted)
                  if modified:
                      comparison['modified_values'][key] = (info[0], modified)
          else:
              comparison['created_keys'][key] = info
  
      for key in registry0.keys():
          if key not in registry1:
              comparison['deleted_keys'].append(key)
  
      return comparison