Until 3472.0 generations ago, the population of deme D was 1072. At that point, it changed to 5884, where it has stayed up to now.
time_units: generations
demes:
  - name: D
    start_time: .inf
    epochs:
      - start_size: 1072
        end_time: 3472.0
      - start_size: 5884
        end_time: 0