Update diff_views_of_binary_tree.py

Author: lighting9999

data_structures/binary_tree/diff_views_of_binary_tree.py

@@ -106,7 +106,6 @@ def depth_first_search(
     depth_first_search(root, 0, left_view)
     return left_view
 
-
 def binary_tree_top_side_view(root: TreeNode) -> list[int]:
     r"""
     Function returns the top side view of binary tree.
@@ -173,8 +172,6 @@ def binary_tree_bottom_side_view(root: TreeNode) -> list[int]:
     >>> binary_tree_bottom_side_view(None)
     []
     """
-    from collections import defaultdict
-
     def breadth_first_search(root: TreeNode, bottom_view: list[int]) -> None:
         """
         A breadth first search traversal with defaultdict ds to append