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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_all_role_config_groups(resource_root, service_name, cluster_name="default"):
 """ Get all role config groups in the specified service. @param resource_root: The root Resource object. @param service_name: Service name. @param cluster_name: Cluster name. @return: A list of ApiRoleConfigGroup objects. @since: API v3 """

  return call(resource_root.get,
      _get_role_config_groups_path(cluster_name, service_name),
      ApiRoleConfigGroup, True, api_version=3)