Serialised dictionary in GET query parameters

I have a query parameter as 

```

  filter: { hello: "world" }

```

which I use as 

```

  filter: json.dumps({filter: { hello: "world" }})

```

when I am making a GET request and parse it at the server [ in simple terms, serialising the entire dict as string and parsing as dict at the server ] . The dict structure is well defined, so I am able to write a schema for it . But how do I define the serialisation . This (link)[https://swagger.io/docs/specification/serialization/] did not help me much 😞

  P.S I have the same issue with array where I use python's json.dump to serialise them before sending