diff --git a/src/client.py b/src/client.py
--- a/src/client.py
+++ b/src/client.py
@@ -29,7 +29,7 @@ class Connection:
 
 
 def negotiate():
-	localTree=HashTree.fromFile(open(filename,mode="rb"))
+	localTree=HashTree.fromFile(filename)
 	blocksToTransfer=[]
 	nodeStack=collections.deque([0]) # root