Simplify if

pupy/network/lib/base.py

@@ -17,6 +17,7 @@ class Circuit(object):
             self.upstream=stream.upstream
             self.stream=stream
         self.transport=transport
+
     def close(self):
         self.transport.on_close()
         self.stream.close()
@@ -33,7 +34,13 @@ class BasePupyTransport(object):
             self.downstream=stream.downstream
             self.upstream=stream.upstream
             self.stream=stream
-        self.circuit=Circuit(self.stream, self, downstream=self.downstream, upstream=self.upstream)
+
+        self.circuit = Circuit(
+            self.stream,
+            self,
+            downstream=self.downstream,
+            upstream=self.upstream)
+
         self.cookie=None
         self.closed=False
 
@@ -174,22 +181,25 @@ class TransportWrapper(BasePupyTransport):
         super(TransportWrapper, self).close()
 
     def downstream_recv(self, data, idx=0):
+        if not len(data):
+            return
+
         if idx > len(self.chain) - 1:
-            if len(data):
             data.write_to(self.upstream)
         else:
-            if len(data):
             try:
                 self.chain[idx].downstream_recv(data)
             except ReleaseChainedTransport:
-                    self.chain = self.chain[:idx] + self.chain[idx+1:]
+                del self.chain[idx]
                 self._setup_callbacks()
 
     def upstream_recv(self, data, idx=None):
+        if not len(data):
+            return
+
         if idx is None:
             idx = len(self.chain) - 1
 
-        if len(data):
         if idx < 0:
             data.write_to(self.downstream)
         else: