some small changes

01_binary_search_trees/bst.py

@@ -31,7 +31,7 @@ class BinarySearchTree():
                     node = node.right_child
                     is_left = False
 
-            # we achieved a leaf
+            # we reached a leaf
             node = BinarySearchNode(value, ptr_node)
             if is_left:
                 ptr_node.left_child = node
@@ -40,6 +40,7 @@ class BinarySearchTree():
 
         self.size += 1
 
+
 class BinarySearchNode():
     """
     Defines any node of the Binary Search Tree.
@@ -54,7 +55,7 @@ class BinarySearchNode():
         self.right_child = None
 
     def has_left_child(self):
-        return not(self.left_child is None)
+        return self.left_child is not None
 
     def has_right_child(self):
         return self.right_child is not None

01_binary_search_trees/bst_test.py

@@ -50,7 +50,6 @@ class test_binary_search_tree(unittest.TestCase):
 
         node = bst.root_node  # we have 6
         self.assertEqual(node.value, node_val1)
-        print node.left_child, node.value
         self.assertTrue(node.has_left_child())
         self.assertEqual(node.left_child.value, node_val2)
         self.assertTrue(node.has_right_child())