Flutter Error: The method 'jsonEncode' is not defined

I am attempting to create a put request to an API using Flutter using the following function:

Future<http.Response> login(String username, String password) {
    return http.put(
        Uri.parse('apiurl'),
        headers: <String, String>{
          'Content-Type': 'application/json; charset=UTF-8',
        },
        body: jsonEncode(
            <String, String>{'username': username, 'password': password}));
  }

The issue I am running into is that it keeps erroring out at the jsonEncode line, saying it is not defined. I have included the following packages:

import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;

What am I missing to make the jsonEncode function exist?

>Solution :

You need to import:

import "dart:convert";

• Dart-convert-library