Takes a grammY bot and returns an update fetcher function for it. The returned function has built-in retrying behavior that can be configured. After every successful fetching operation, the offset parameter is correctly incremented. As a result, you can simply invoke the created function multiple times in a row, and you will obtain new updates every time.

The update fetcher function has a default long polling timeout of 30 seconds. Specify sourceOptions to configure what values to pass to getUpdates calls.