'Generate legal XHTML anchor for series names.
Flatten series name to ascii_legal text.
Args:
series (str): series name
Return:
(str): asciized version of series name'

def generate_series_anchor(self, series):

    if (self.letter_or_symbol(series) == self.SYMBOLS):
        return ('symbol_%s_series' % re.sub('\\W', '', series).lower())
    else:
        return ('%s_series' % re.sub('\\W', '', ascii_text(series)).lower())
