[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

@@ -3,8 +3,10 @@
 trie (prefix tree) in whicheach node that is the only child is merged
 with its parent [https://en.wikipedia.org/wiki/Radix_tree]
 """
+
 import unittest
 
+
 class RadixNode:
     def __init__(self, prefix: str = "", is_leaf: bool = False) -> None:
         # Mapping from the first character of the prefix of the node
@@ -195,9 +197,11 @@ def print_tree(self, height: int = 0) -> None:
         for value in self.nodes.values():
             value.print_tree(height + 1)
 
+
 ## write unit test for the code using unittest library with logic similar to test_trie() function
 ## and call it from main()
 
+
 class TestRadixNode(unittest.TestCase):
     def test_trie(self) -> None:
         words = "banana bananas bandana band apple all beast".split()
@@ -212,13 +216,12 @@ def test_trie(self) -> None:
         root.delete("banana")
         self.assertFalse(root.find("banana"))
         self.assertTrue(root.find("bananas"))
-    
 
     def test_trie_2(self) -> None:
-        '''
-        now add a new test case which inserts 
+        """
+        now add a new test case which inserts
         foobbb, fooaaa, foo in the given order and checks for different assertions
-        ''' 
+        """
         words = "foobbb fooaaa foo".split()
         root = RadixNode()
         root.insert_many(words)
@@ -229,5 +232,6 @@ def test_trie_2(self) -> None:
         self.assertTrue(root.find("foobbb"))
         self.assertTrue(root.find("fooaaa"))
 
+
 if __name__ == "__main__":
     unittest.main()