$ pyenv install 3.5.1 $ pyenv virtualenv 3.5.1 mpl35 $ pyenv activate mlp35 $ pip install matplotlib numpy scipy $ python -c "import matplotlib.pyplot" Traceback (most recent call last): File "<string>", line 1, in <module> File "/Users/kodairatomonori/.pyenv/versions/mpl35/lib/python3.5/site-packages/matplotlib/pyplot.py", line 114, in <module> _backend_mod, new_figure_manager, draw_if_interactiv