When I tried to run matplotlib with pypy3, I got the following error. pypy version [PyPy 7.3.1 with GCC 9.3.0]. Matplotlib version
matplotlib-3.3.4-pp36-pypy36_pp73-manylinux2010_x86_64.whl

from . import ft2font
pypy3.6/site-packages/matplotlib/ft2font.pypy36-pp73-x86_64-linux-gnu.so: undefined symbol: PyPyUnicode_ReadChar