pyln: add getroutes wrapper to pyln-client, add single_route helper to pyln-testing.

diff --git a/contrib/pyln-client/pyln/client/lightning.py b/contrib/pyln-client/pyln/client/lightning.py
index 76b8eb8e..5b72fa64 100644
--- a/contrib/pyln-client/pyln/client/lightning.py
+++ b/contrib/pyln-client/pyln/client/lightning.py
@@ -896,6 +896,24 @@ class LightningRpc(UnixDomainSocketRpc):
         }
         return self.call("getroute", payload)
 
+    def getroutes(self, source, destination, amount_msat, layers, maxfee_msat,
+                  final_cltv, maxdelay=None, maxparts=None):
+        """Find routes from {source} to {destination} for {amount_msat},
+        applying {layers}, paying no more than {maxfee_msat},
+        ending in {final_cltv}.
+        """
+        payload = {
+            "source": source,
+            "destination": destination,
+            "amount_msat": amount_msat,
+            "layers": layers,
+            "maxfee_msat": maxfee_msat,
+            "final_cltv": final_cltv,
+            "maxdelay": maxdelay,
+            "maxparts": maxparts,
+        }
+        return self.call("getroutes", payload)
+
     def help(self, command=None):
         """
         Show available commands, or just {command} if supplied.
diff --git a/contrib/pyln-testing/pyln/testing/utils.py b/contrib/pyln-testing/pyln/testing/utils.py
index 861afcea..1065838c 100644
--- a/contrib/pyln-testing/pyln/testing/utils.py
+++ b/contrib/pyln-testing/pyln/testing/utils.py
@@ -1363,7 +1363,7 @@ class LightningNode(object):
         start_time = time.time()
         while time.time() < start_time + timeout:
             try:
-                self.rpc.getroute(destination.info['id'], 1, 1)
+                self.single_route(destination.info['id'], 1)
                 return True
             except Exception:
                 time.sleep(1)
@@ -1383,20 +1383,10 @@ class LightningNode(object):
                     wait_for(lambda: len(self.rpc.listpeerchannels(peer["id"])['channels'][idx]['htlcs']) == 0)
 
     # This sends money to a directly connected peer
-    # if `route` is `True`, it can also send over the network.
-    def pay(self, dst, amt, label=None, route=False):
+    def pay(self, dst, amt, label=None):
         if not label:
             label = ''.join(random.choice(string.ascii_letters + string.digits) for _ in range(20))
 
-        if route is True:
-            invoice = dst.rpc.invoice(amt, label, "desc")
-            route = self.rpc.getroute(dst.info["id"], amt, riskfactor=0, fuzzpercent=0)
-            self.rpc.sendpay(route["route"], invoice["payment_hash"], payment_secret=invoice.get('payment_secret'))
-            result = self.rpc.waitsendpay(invoice["payment_hash"])
-            assert result.get('status') == 'complete'
-            self.wait_for_htlcs()
-            return
-
         # check we are connected
         dst_id = dst.info['id']
         assert len(self.rpc.listpeers(dst_id).get('peers')) == 1
@@ -1428,6 +1418,16 @@ class LightningNode(object):
         # Make sure they're all settled, in case we quickly mine blocks!
         dst.wait_for_htlcs()
 
+    def single_route(self, node_id, amount_msat, cltv=9):
+        """Similar to the getroute() call (different output though!)"""
+        return only_one(self.rpc.getroutes(source=self.info['id'],
+                                           destination=node_id,
+                                           amount_msat=amount_msat,
+                                           layers=["auto.localchans", "auto.sourcefree"],
+                                           maxfee_msat=10000000,
+                                           final_cltv=cltv,
+                                           maxparts=1)['routes'])['path']
+
     # This helper sends all money to a peer until even 1 msat can't get through.
     def drain(self, peer):
         total = 0