How to deliver the capability of code without delivering the code itself?

I am doing the following step sequentially in Python: i. read data ii. preprocess them (deal for NAs, etc) iii. split them into training and test set iv. train and test a machine learning model to do some classification on the data.

We would like to hand the capability of the code (not the code itself) to another team as part of a project. What deliverable can we give the team? It should accept the data as input (step i.), next perform steps ii. to iv., and return the classification result (a label, like "0" or "1") as output. Steps ii. to iv. should not be revealed. I am looking for a way to create a black box that we can hand over that performs steps i to iv without giving away the code.

A web service with a well defined API would be a good solution, but how could we package and deliver this physically, like in a file, to the team we are working with? Would containers act like a black box? Would it be better to create some sort of executable from the Python code? What options are there? And would they also work for other languages such as R or bash?