Add a requirements.txt

[asimsalam]

At this time, there are multiple failures that can be encountered in the code base due to difference in dependency versions like matplotlib.
A requirements.txt file should be added in the project to list the dependencies and their versions compatible with the code base so users can easily run the examples and exercises.

[freecrazybb7]

ERROR: git+https://github.com/orlandpm/Math-for-Programmers.git does not appear to be a Python project: neither 'setup.py' nor 'pyproject.toml' found.

how to solve this problem？
thanks

[christopherMills]

Second this - would solve so many issues.