'Set the font family.  May be either a single string, or a list
of strings in decreasing priority.  Each string may be either
a real font name or a generic font class name.  If the latter,
the specific font names will be looked up in the
:file:`matplotlibrc` file.
ACCEPTS: [FONTNAME | \'serif\' | \'sans-serif\' | \'cursive\' | \'fantasy\' |
\'monospace\' ]'

def set_family(self, fontname):

    self._fontproperties.set_family(fontname)
    self.stale = True
