post method
Implementation
Future<TransactionRequestResponse> post({required String account}) async {
final response = await http.post(
link,
headers: {'Accept': 'application/json', 'Content-Type': 'application/json'},
body: jsonEncode({'account': account}),
);
if (response.statusCode != 200) {
throw HttpException(response.statusCode, response.body);
}
// ignore: avoid-type-casts, controlled type
return TransactionRequestResponse.fromJson(json.decode(response.body) as Map<String, dynamic>);
}