def head_option(self):
        if not self.sequence:
            return None
        return self.head()
See :meth:`I18n.format_date`.
dataset/ETHPy150Open EntilZha/PyFunctional/functional/pipeline.py/Sequence.head_option--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/lib/webapp2-2.3/webapp2_extras/i18n.py/format_date