I have Windows 7.
For some reason, f2tfont.cpp does not compile when installing matplotlib (through pip), hence, the matplotlib install fails. Also, the
As specified in PEP 11, a Python release only supports a Windows platform while Microsoft considers the platform under extended support. This means that Python 3.7 supports Windows Vista and newer. If you require Windows XP support then please install Python 3.4.
In case Windows Service Pack isn't installed. You can download Windows 7 Service Pack 1 (SP1) manually from here or also you can download it from Windows Update of Windows 7.
So, you need to install Microsoft Visual C++ redistribution 2015 from here.
You don't need to install Microsoft Visual Studio just C++ redistributions of 2015 will do the job.