Today, the vast majority of businesses implement their commission plan models in Microsoft Excel, Google Sheets, or some other spreadsheet software. In this challenge, you will implement a simplified spreadsheet system that can be used to implement an extremely simple financial model.

• Implement a web server with a RESTful API that models a spreadsheet supporting cells, values, and formulas.
• For simplicity, the size of the spreadsheet can be assumed to be fixed to 10 rows and 10 columns.
  • Columns are named after capital letters, starting with "A".
  • Rows are numbered and increasing, starting from "1".
• The state of the spreadsheet should be mutatable via API calls.
• After a given API call to update a cell, update any affected cells with their newly computed values.
• Cell updates should take as input either an integer or a simple formula that references other cells and only needs to support addition.
  • For example, -1 and 123 should be able to be stored in a cell.
  • =A1+B1 should be able to be stored in a cell, and the display value should be the result of evaluating the sum of the value in A1 and the value in B1.

• Don't worry about handling multiple concurrent users viewing and editing the spreadsheet at the same time.

The sample code distributed with this package is provided to you as a starting point if you'd like to use it.

1. Set up your virtualenv: python3 -mvenv venv
2. Source the activate script: source venv/bin/activate
3. Install the dependencies in your virtualenv: pip install -r requirements.txt
4. Run the server FLASK_DEBUG=1 FLASK_APP=server.py flask run