diff --git a/src/tests/test_hashtree.py b/src/tests/test_hashtree.py
--- a/src/tests/test_hashtree.py
+++ b/src/tests/test_hashtree.py
@@ -9,23 +9,23 @@ random.seed(17)
 
 
 def buildTree(leaves):
-	tree=HashTree(len(leaves))
+	tree = HashTree(len(leaves))
 	for l in leaves:
 		tree.insertLeaf(l)
 	tree.buildTree()
 	return tree
 
 
-class TestMorevna(RedirectedOutput,TestCase):
+class TestMorevna(RedirectedOutput, TestCase):
 	def test_batchUpdate(self):
-		leaves=[b"a" for i in range(8)]
-		t1=buildTree(leaves)
-		keys=list(range(8))
+		leaves = [b"a" for i in range(8)]
+		t1 = buildTree(leaves)
+		keys = list(range(8))
 
 		for i in range(8):
 			random.shuffle(keys)
 			for k in keys[:i+1]:
-				leaves[k]=bytes([random.randrange(256)])
-			t2=buildTree(leaves)
-			t1.batchUpdate((k+t1.leafStart,leaves[k]) for k in keys[:i+1])
-			self.assertEqual(t1.store,t2.store)
+				leaves[k] = bytes([random.randrange(256)])
+			t2 = buildTree(leaves)
+			t1.batchUpdate((k+t1.leafStart, leaves[k]) for k in keys[:i+1])
+			self.assertEqual(t1.store, t2.store)