How would you design and implement a Dynamic Pricing System for *Digikala*? The Dynamic Pricing System should use machine learning to intelligently select which products should receive a discount for which users and how much that discount should be. You must optimize for both customer satisfaction and total profit per customer. Describe the strategy, algorithm, tools, open-source, and language you would use. Also, describe the metrics that you would use to test it. Upload the description of your solution as a *PDF* file. It'll be evaluated manually. Your description can be in Farsi.