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

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graphs/directed_and_undirected_weighted_graph.py

@@ -10,12 +10,12 @@ Useful Links: https://www.geeksforgeeks.org/applications-advantages-and-disadvan
               https://en.wikipedia.org/wiki/Graph_(discrete_mathematics)
 """
 
-
 from collections import deque
 from math import floor
 from random import random
 from time import time
 
+
 class DirectedGraph:
     def __init__(self):
         self.graph = {}