@Substitution(name='groupby')
    @Appender(_doc_template)
    def pad(self, limit=None):
        return self.apply(lambda x: x.ffill(limit=limit))
De-Serializes JSON Dict to OpenFlow physical port
dataset/ETHPy150Open pydata/pandas/pandas/core/groupby.py/GroupBy.pad--crossover with--dataset/ETHPy150Open ucb-sts/sts/sts/entities/base.py/deserialize_ofp_phy_port