Fix bs_fqme using venue and expiry

piker/brokers/deribit/api.py

@@ -279,10 +279,6 @@ class Client:
 
         self.json_rpc = json_rpc
 
-    @property
-    def currencies(self):
-        return ['btc', 'eth', 'sol', 'usd']
-
     async def get_balances(
         self,
         kind: str = 'option'

piker/brokers/deribit/venues.py

@@ -116,13 +116,19 @@ class OptionPair(Pair, frozen=True, kw_only=True):
     # NOTE: see `.data._symcache.SymbologyCache.load()` for why
     ns_path: str = 'piker.brokers.deribit:OptionPair'
 
+    @property
+    def expiry(self) -> str:
+        symbol: str = self.instrument_name.lower()
+        pair, expiry, strike_price, otype = symbol.split('-')
+        return f'{expiry}'
+
     @property
     def venue(self) -> str:
         return 'OPTION'
 
     @property
     def bs_fqme(self) -> str:
-        return f'{self.symbol}'
+        return f'{self.symbol}.{self.venue}.{self.expiry}'
 
     @property
     def bs_src_asset(self) -> str: