Update README.md

[Velcon-Zheng]

All Submissions

• Is the code you are submitting your own work?
• Have you followed the contributing guidelines?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

New Model Submissions

• Is the code you are submitting your own work?
• Did you properly attribute the authors of any code you referenced?
• Did you write unit tests for your new model?
• Does your submission pass the unit tests?
• Did you write documentation for your new model?
• Have you formatted your code using the black deaults?

Changes to Existing Models

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes, as applicable?
• Have you successfully ran tests with your changes locally?