Custom API with a Dictionary Type?

[oucfei]

So I'm building an power app with a custom API (from a swagger definition). Everything is fine except that in the API, one of the response fields is a Dictionary type in C# (Dictionary<String, String>). In the swagger definition the Dictionary type is represented like this (from http://swagger.io/specification😞

{
  "type": "object",
  "additionalProperties": {
    "type": "string"
  }
}

 now in power apps, how can I get the value of the dictionary type (like all the keys and their values)? 

Thanks in advance for your help!