def list_by_service(resource_group_name, service_name, custom_headers:nil)
      first_page = list_by_service_as_lazy(resource_group_name, service_name, custom_headers:custom_headers)
      first_page.get_all_items
    end
def list_by_service(resource_group_name, service_name, custom_headers:nil)
      first_page = list_by_service_as_lazy(resource_group_name, service_name, custom_headers:custom_headers)
      first_page.get_all_items
    end
Lists a collection of Identity Provider configured in the specified service
 instance.

 @param resource_group_name [String] The name of the resource group.
 @param service_name [String] The name of the API Management service.
 @param custom_headers [Hash{String => String}] A hash of custom headers that
 will be added to the HTTP request.

 @return [Array<IdentityProviderContract>] operation results.