toMap method
Creates a Map<String, dynamic> map
representation of this instance.
This can be useful for saving the instance in a database.
Implementation
Map<String, dynamic> toMap() => <String, dynamic>{
_brandKey: brand,
_categoryKey: category,
_costKey: '$cost',
_descriptionKey: description,
_idKey: id,
_nameKey: name,
_originKey: origin?.string(),
_priceKey: '$price',
};