Dynamic parameter or lookup parameter in matrix circleci job

I have a matrix circleci job, currently it only takes in one param for a market, that market is hard coded to a region, but I would like to expand it so that any additional market is mapped to a specific region:

  - infra_market_plan:
      name: infra-plan-web-app-<< matrix.market >>-<< matrix.environment >>
      matrix:
        parameters:
          market: ["pe"]
          environment: ["staging", "prod"]
          infra_directory: ["web-app"]
      context: maverick-aws
      requires:
        - infra-plan-global-<< matrix.environment >>
      filters:
        branches:
          ignore: main

so in the code above, I want “pe” to map to “eu-west-1”, but if I add “uk” as a market I would like that to map tp “eu-west-2”, how could I achieve that here?