Assignment

HP Norton has been using comma-separated files (.CSV extension) to keep track of which furniture they have rented out to which customer. This is currently generated from a spreadsheet called inventory.

Your Project Manager wants you to get the spreadsheet program out of the equation by creating a Python function that will create and update an inventory CSV file with all the information that is currently entered through the spreadsheet program. You have decided to use closures and currying to develop the necessary functionality.

You will also develop functionality to to bulk-process a list of items, coming from a separate CSV file, that have been rented out to a single customer. This functionality will thus update the inventory list by adding that customer’s rentals.

To summarize: 1. You will create a program to initially create, and subsequently update, a CSV file that lists which furniture is rented to which customer (to replace use of the spreadsheet mentioned above). 2. You will create additionally functionality that will load individual customers rentals.

Here is what you need to do:

  1. Create a python module called inventory.py, to replace the existing spreadsheet. This file will contain all the functions used for this assignment.

  2. Create a function called add_furniture that takes the following input parameters:

    • invoice_file

    • customer_name

    • item_code

    • item_description

    • item_monthly_price

    This function will create invoice_file (to replace the spreadsheet’s data) if it doesn’t exist or append a new line to it if it does. After adding a few items to the same file, the file created by add_furniture should look something like this:

    Elisa Miles,LR04,Leather Sofa,25.00
Edward Data,KT78,Kitchen Table,10.00
Alex Gonzales,BR02,Queen Mattress,17.00

    You can create a starter file in this format for testing, or you can have your add function do it.

  3. Create a function called single_customer:

    • Input parameters: customer_name, invoice_file.

    • Output: Returns a function that takes one parameter, rental_items.

    single_customer needs to use functools.partial and closures, in order to return a function that will iterate through rental_items and add each item to invoice_file.

Other requirements:

  • Your code should not trigger any warnings or errors from Pylint.

Testing

You can create the test_items.csv file for testing of your single_customer function. The layout of the csv will be something like this:

LR04,Leather Sofa,25.00
KT78,Kitchen Table,10.00
BR02,Queen Mattress,17.00

add_furniture can be tested manually, as shown below.

The idea is for the single_customer() function to return a new function (with a fixed customer name and destination inventory file) that will add all items in a source file to the overall inventory under a single customer name. Internally, single_customer() should leverage add_furniture() by fixing the first two parameters.

from inventory import *
add_furniture("rented_items.csv", "Elisa Miles", "LR04", "Leather Sofa", 25)
add_furniture("rented_items.csv", "Edward Data", "KT78", "Kitchen Table", 10)
add_furniture("rented_items.csv", "Alex Gonzales", "Queen Mattress", 17)
create_invoice = single_customer("Susan Wong", "rented_items.csv")
create_invoice("test_items.csv")

So, using create_invoice() will, in this case, add all items in test_items.csv to rented_items.csv under the name “Susan Wong”.

Submission

Your submission should include a single file, inventory.py with two functions, add_furniture and single_customer. You can include other functions but all testing for the purpose of grading your assignment will use only those two functions.