I want mlx.optimizers.MultiOptimizer(optimizers, filters= ) as a stateful optimizer wrapper that lets me…

I want mlx.optimizers.MultiOptimizer(optimizers, filters= ) as a stateful optimizer wrapper that lets me…: a task in MiMo-V2.6-RL-harbor-code: MiMo-V2.6-RL Code (Harbor) (Harbor dataset). MultiOptimizer.init(parameters: dict) should split the parameter tree by the predicates and initialize each…

The task

`MultiOptimizer.init(parameters: dict)` should split the parameter tree by the predicates and initialize each wrapped optimizer only with the parameters assigned to it, using the final optimizer as the fallback for anything that did not match an earlier predicate. `MultiOptimizer.apply_gradients(gradients: dict,…

Part of FineEnvs/MiMo-V2.6-RL-harbor-code.