code: def update_mutation_inputs(service):
      
      # grab the default list of field summaries
      inputs = _service_mutation_summaries(service)
  
      # visit each field
      for field in inputs:
          # if we're looking at the id field
          if field['name'] == 'id':
              # make sure its required
              field['required'] = True
          # but no other field
          else:
              # is required
              field['required'] = False
  
      # return the final list
      return inputs
docs: Args:
              service : The service being updated by the mutation
          Returns:
              (list) : a list of all of the fields availible for the service. Pk
                  is a required field in order to filter the results