toJson method
Implementation
Map<String, dynamic> toJson() => {
'id': id,
'number': number,
'issuanceDate': issuanceDate,
'expiryDate': expiryDate,
'issuanceCountry': issuanceCountry,
'issuanceLocation': issuanceLocation,
'nationality': nationality,
'documentType': documentType,
'birthPlace': birthPlace,
'holder': holder,
};