error when i write pip install -r requirements.txt

[PandyaDeval]

This is the error:

Command "python setup.py egg_info" failed with error code 1 in C:\Users\Lenovo\AppData\Local\Temp\pip-install-ad04rycf\matplotlib\

[mCornish]

I found a solution for anyone else who runs into this issue:

First of all, I'm on Windows 10; I'm guessing that's a factor here.

I Googled around and tried a bunch of solutions involving installing and upgrading; none of those worked.

Ultimately, I ended up just manually installing the dependencies found in requirements.txt, as well as scipy (which is apparently also a dependency):
pip install -U matplotlib numpy pandas scipy scikit-learn

After that, I was able to run python demo.py.

I haven't actually started working on the challenge yet, so I'll update this if I run into anymore issues.