docs: def delete(ctx, family_file, family_type, case_id):
      """Delete the variants of a case."""
      if not (family_file or case_id):
          LOG.error("Please provide a family file")
          ctx.abort()
  
      adapter = ctx.obj['adapter']
  
      # Get a ped_parser.Family object from family file
      family = None
      family_id = None
      if family_file:
          with open(family_file, 'r') as family_lines:
              family = get_case(
                  family_lines=family_lines,
                  family_type=family_type
              )
              family_id = family.family_id
  
      # There has to be a case_id or a family at this stage.
      case_id = case_id or family_id
  
      if not case_id:
          LOG.warning("Please provide a case id")
          ctx.abort()
  
      existing_case = adapter.case({'case_id': case_id})
      if not existing_case:
          LOG.warning("Case %s does not exist in database" %case_id)
          context.abort
  
  
      start_deleting = datetime.now()
      try:
          delete_command(
              adapter=adapter,
              case_obj=existing_case,
          )
      except (CaseError, IOError) as error:
          LOG.warning(error)
          ctx.abort()