.payee_pub_key(our_node_pubkey)
.payment_hash(Hash::from_slice(&payment_hash.0).unwrap())
.payment_secret(payment_secret)
+ .basic_mpp()
.min_final_cltv_expiry(MIN_FINAL_CLTV_EXPIRY.into());
if let Some(amt) = amt_msat {
invoice = invoice.amount_pico_btc(amt * 10);