diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index e4c81a5ec..76ee1312f 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -155,6 +155,8 @@ We want your work to be readable by others; therefore, we encourage you to note
       return a + b
   ```
 
+  Instructions on how to install mypy can be found [here](https://github.com/python/mypy). Please use the command `mypy --ignore-missing-imports .` to test all files or `mypy --ignore-missing-imports path/to/file.py` to test a specific file.
+
 - [__List comprehensions and generators__](https://docs.python.org/3/tutorial/datastructures.html#list-comprehensions) are preferred over the use of `lambda`, `map`, `filter`, `reduce` but the important thing is to demonstrate the power of Python in code that is easy to read and maintain.
 
 - Avoid importing external libraries for basic algorithms. Only use those libraries for complicated algorithms.