code: def from_str(action: str, resource: str=None):
          
          if resource:
              return Scope('{}:{}'.format(action, resource))
          else:
              return Scope(action)
docs: Return a scope based on the supplied action and resource.
  
          :param action: the scope action eg. read, write or admin
          :param resource: the specific resource of the scope, if any eg. alerts,
              blackouts, heartbeats, users, perms, customers, keys, webhooks,
              oembed, management or userinfo or None
          :return: Scope