In [1]: %paste
import matplotlib.font_manager
flist = matplotlib.font_manager.get_fontconfig_fonts()
names = [matplotlib.font_manager.FontProperties(fname=fname).get_name() for fname in flist]
print('Bitstream Vera Sans' in names)

## -- End pasted text --
/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/matplotlib/font_manager.py:273: UserWarning: Matplotlib is building the font cache using fc-list. This may take a moment.
  warnings.warn('Matplotlib is building the font cache using fc-list. This may take a moment.')
---------------------------------------------------------------------------
RuntimeError                              Traceback (most recent call last)
<ipython-input-1-d6f6752cbc94> in <module>()
      1 import matplotlib.font_manager
      2 flist = matplotlib.font_manager.get_fontconfig_fonts()
----> 3 names = [matplotlib.font_manager.FontProperties(fname=fname).get_name() for fname in flist]
      4 print('Bitstream Vera Sans' in names)

<ipython-input-1-d6f6752cbc94> in <listcomp>(.0)
      1 import matplotlib.font_manager
      2 flist = matplotlib.font_manager.get_fontconfig_fonts()
----> 3 names = [matplotlib.font_manager.FontProperties(fname=fname).get_name() for fname in flist]
      4 print('Bitstream Vera Sans' in names)

/opt/local/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/matplotlib/font_manager.py in get_name(self)
    735         properties.
    736         """
--> 737         return ft2font.FT2Font(findfont(self)).family_name
    738 
    739     def get_style(self):

RuntimeError: In FT2Font: Could not set the fontsize