code: func (n *NamedStmt) Query(arg interface{}) (*sql.Rows, error) {
  	args, err := bindAnyArgs(n.Params, arg, n.Stmt.Mapper)
  	if err != nil {
  		return nil, err
  	}
  	return n.Stmt.Query(args...)
  }
docs: // Query executes a named statement using the struct argument, returning rows.
  // Any named placeholder parameters are replaced with fields from arg.