How to install matplotlib?

[snippsat]

pip uninstall numpy

Then:

pip install matplotlib

If i do a quick with virtual environment,venv is now build into Python.
Then do pip freeze after install.

(install_env) C:\code\install_env   
λ pip freeze                        
cycler==0.10.0                      
kiwisolver==1.0.1                   
matplotlib==3.0.3                   
numpy==1.16.2                       
pyparsing==2.3.1                    
python-dateutil==2.8.0              
six==1.12.0

You see that pip install matplotlib automatic install a never version that numpy 1.5.