The Owner's Report

A bakery keeps one table of orders per month. The orders only store a product number. The prices are in a separate product list. The owner wants one report: how much money each city made in each month, plus a total.

Task: write revenue_report(months, products).

• months is a dictionary from a month's name to that month's orders. Each month's orders are a dictionary of three lists: "city", "product_id" and "qty". Every month has at least one order.
• products is a dictionary of three lists: "product_id", "name" and "price". Every product_id used in an order is in it, once.
• An order's revenue is its qty times its product's price.
• Return a list of rows, one per city that appears in any month. Each row is [city, revenue in month 1, revenue in month 2, ..., total], with the months in the same order as the keys of months.
• A city with no orders in a month has 0.0 for that month.
• Every money value is a float rounded to 2 decimal places.
• Sort the rows by total, biggest first. If two cities have the same total, put them in alphabetical order.