I believe you just pass objects instead, like you would in OOP, and take the hit of pickling and unpickling them every time. If you really want to pass lambdas

I believe you just pass objects instead, like you would in OOP, and take the hit of pickling and unpickling them every time. If you really want to pass lambdas, you can use a third party library to pickle them https://github.com/cloudpipe/cloudpickle https://github.com/cloudpipe/cloudpickle Yes, this is not great.