docs: def generate_arn(
          service, resource, partition='aws',
          region=None, account_id=None, resource_type=None, separator='/'):
      """Generate an Amazon Resource Name.
      See http://docs.aws.amazon.com/general/latest/gr/aws-arns-and-namespaces.html.
      """
      if region and region in REGION_PARTITION_MAP:
          partition = REGION_PARTITION_MAP[region]
      if service == 's3':
          region = ''
      arn = 'arn:%s:%s:%s:%s:' % (
          partition, service, region if region else '', account_id if account_id else '')
      if resource_type:
          arn = arn + '%s%s%s' % (resource_type, separator, resource)
      else:
          arn = arn + resource
      return arn