Add suport testnet4

electrum/constants.py

@@ -155,6 +155,17 @@ class BitcoinTestnet(AbstractNet):
     ]
 
 
+class BitcoinTestnet4(BitcoinTestnet):
+
+    NET_NAME = "testnet4"
+    SEGWIT_HRP = "tb"
+    BOLT11_HRP = SEGWIT_HRP
+    GENESIS = "00000000da84f2bafbbc53dee25a72ae507ff4914b867c565be350b0da8bf043"
+    DEFAULT_SERVERS = read_json('servers_testnet4.json', {})
+    CHECKPOINTS = read_json('checkpoints_testnet4.json', [])
+    LN_DNS_SEEDS = []
+
+
 class BitcoinRegtest(BitcoinTestnet):
 
     NET_NAME = "regtest"
@@ -211,6 +222,10 @@ def set_testnet():
     global net
     net = BitcoinTestnet
 
+def set_testnet4():
+    global net
+    net = BitcoinTestnet4
+
 def set_regtest():
     global net
     net = BitcoinRegtest