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

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

Author: pre-commit-ci[bot]

data_structures/trie/radix_tree.py

@@ -198,7 +198,7 @@ def print_tree(self, height: int = 0) -> None:
             value.print_tree(height + 1)
 
 
-## write unit test for the code using unittest library with 
+## write unit test for the code using unittest library with
 ## logic similar to test_trie() function
 ## and call it from main()