Add currency symbol to Contribution.getbalance

api/v3/Contribution/Getbalance.php

@@ -17,6 +17,8 @@ function civicrm_api3_contribution_getbalance($params) {
     'return' => 'currency',
     'id' => $params['id'],
   ]);
+  $result['currencySymbol'] = CRM_Core_BAO_Country::defaultCurrencySymbol($result['currency']);
+
   return civicrm_api3_create_success($result, $params);
 }