func (s *Series) HasExpression() bool {
	if s != nil && s.Expression != nil {
		return true
	}

	return false
}
func (s *Series) HasExpression() bool {
	if s != nil && s.Expression != nil {
		return true
	}

	return false
}
func ( s * Series ) HasExpression ( ) bool { if s != nil && s . Expression != nil { return true } return false }
// HasExpression returns a boolean if a field has been set.
HasExpression returns a boolean if a field has been set .