def current_low_feerate_per_kw_srk_channel(self) -> Optional[int]:
        """Gets low feerate for static remote key channels."""
        if constants.net is constants.BitcoinRegtest:
            feerate_per_kvbyte = 0
        else:
            if not self.network.fee_estimates.has_data():
                return None
            feerate_per_kvbyte = self.network.fee_estimates.eta_target_to_fee(FEE_LN_LOW_ETA_TARGET) or 0
        low_feerate_per_kw = max(FEERATE_PER_KW_MIN_RELAY_LIGHTNING, feerate_per_kvbyte // 4)
        # make sure this is never higher than the target feerate:
        current_target_feerate = self.current_target_feerate_per_kw(has_anchors=False)
        if not current_target_feerate:
            return None
        low_feerate_per_kw = min(low_feerate_per_kw, current_target_feerate)
        return low_feerate_per_kw
Gets low feerate for static remote key channels.
electrum/lnworker.py