move constants to venue

piker/brokers/deribit/api.py

@@ -58,6 +58,7 @@ from cryptofeed.symbols import Symbol
 # types for managing the cb callbacks.
 # from cryptofeed.types import L1Book
 from .venues import (
+    _ws_url,
     MarketType,
     PAIRTYPES,
     Pair,
@@ -95,11 +96,6 @@ _spawn_kwargs = {
 }
 
 
-_url = 'https://www.deribit.com'
-_ws_url = 'wss://www.deribit.com/ws/api/v2'
-_testnet_ws_url = 'wss://test.deribit.com/ws/api/v2'
-
-
 # convert datetime obj timestamp to unixtime in milliseconds
 def deribit_timestamp(when):
     return int((when.timestamp() * 1000) + (when.microsecond / 1000))