extractRevenue function
Implementation
double? extractRevenue(String key, Map<String, dynamic> properties) {
if (properties[key] == null) {
return null;
}
if (properties[key] is double || properties[key] is int) {
return properties[key];
} else if (properties[key] is String) {
return double.parse(properties[key]);
} else {
return null;
}
}