code: func selectInState(b squirrel.SelectBuilder, expr string, values []common.State) squirrel.SelectBuilder {
  	if len(values) == 0 {
  		return b
  	}
  	args := make([]interface{}, len(values))
  	for i, val := range values {
  		args[i] = val
  	}
  	return b.Where(expr+" IN ("+squirrel.Placeholders(len(args))+")", args...)
  }
docs: // selectInState returns the given SELECT modified with a WHERE IN clause.
  // expr is the left-hand side of the IN operator, values is the right-hand side. No-op if values is empty.