'Get a mapping of character codes to glyph ids for the specified glyph
ids.'

def get_glyph_map(self, glyph_ids):

    if (self.bmp_table is None):
        raise UnsupportedFont(u'This    font    has    no    Windows    BMP    cmap    subtable.    Most    likely    a    special    purpose    font.')
    glyph_ids = frozenset(glyph_ids)
    return self.bmp_table.get_glyph_map(glyph_ids)
