[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

Diff for: sorts/tree_sort.py

@@ -44,10 +44,10 @@ def tree_sort(arr):
 
     >>> tree_sort([5, -4, 9, 2, 7])
     [-4, 2, 5, 7, 9]
-    
+
     >>> tree_sort([5, 6, 1, -1, 4, 37, 2, 7])
     [-1, 1, 2, 4, 5, 6, 7, 37]
-    
+
     """
     # Build BST
     if len(arr) == 0:
@@ -65,4 +65,3 @@ def tree_sort(arr):
     import doctest
 
     doctest.testmod()
-