python3-matplotlib 3.5.2-2build1 (riscv64 binary) in ubuntu lunar

 Matplotlib is a pure Python plotting library designed to bring
 publication quality plotting to Python with a syntax familiar to
 Matlab users. All of the plotting commands in the pylab interface can
 be accessed either via a functional interface familiar to Matlab
 users or an object oriented interface familiar to Python users.
 .
 This package contains the Python 3 version of matplotlib.