How was the request's uniqueness ensured with two sources?.

The uniqueness of the request when working with two sources was ensured by generating a unique identifier for each request, which took into account the parameters and the call context.

For example, a combination of key request parameters and hashing could be used to create a unique key, which was then checked to see if such a request had already been made. This prevented duplication and ensured data consistency when merging results from two sources.