code: def delete_process_work_item_type(self, process_id, wit_ref_name):
          
          route_values = {}
          if process_id is not None:
              route_values['processId'] = self._serialize.url('process_id', process_id, 'str')
          if wit_ref_name is not None:
              route_values['witRefName'] = self._serialize.url('wit_ref_name', wit_ref_name, 'str')
          self._send(http_method='DELETE',
                     location_id='e2e9d1a6-432d-4062-8870-bfcb8c324ad7',
                     version='5.0-preview.2',
                     route_values=route_values)
docs: DeleteProcessWorkItemType.
          [Preview API] Removes a work itewm type in the process.
          :param str process_id: The ID of the process.
          :param str wit_ref_name: The reference name of the work item type.