code: def validate_ids(ctx, param, value):
      
      if not value:
          return None
  
      ids = [x.strip() for x in value.split(',')]
      for id_item in ids:
          if not id_item.isdigit():
              raise click.BadParameter('Non-numeric value "{0}" provided for an ID.'.format(id_item))
  
      return ids
docs: Validate a list of IDs and convert them to a list.