purchase screen coupons list final

lib/network.dart

@@ -58,6 +58,17 @@ getPurchaseRequest(String endpoint, Map body, String token) async {
   return httpClient.post(endpoint, body: body, headers: headers);
 }
 
+getCouponsRequest(String endpoint, String token) async {
+
+  var headers = {
+    'DM-Authorization': 'dmapptoken ${await getToken()}',
+    'Authorization': 'dmtoken ${token}',
+    'Accept-Language': Intl.defaultLocale
+  };
+
+  return httpClient.get(endpoint, headers: headers);
+}
+
 getEndpoint() async {
   return await platform.invokeMethod('getEndpoint');
 }