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

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graphs/johnson_graph.py

@@ -2,6 +2,7 @@ from collections import deque
 import heapq
 import sys
 
+
 # First implementation of johnson algorithm
 class JohnsonGraph:
     def __init__(self):
@@ -52,7 +53,6 @@ class JohnsonGraph:
     # perform the johnson algorithm to handle the negative weights that could not be handled by either the dijkstra
     # or the bellman ford algorithm efficiently
     def johnson_algo(self):
-        
         self.add_vertices("#")
         for v in self.graph:
             if v != "#":
@@ -79,6 +79,7 @@ class JohnsonGraph:
             distances.append(new_dist)
         return distances
 
+
 g = JohnsonGraph()
 # this a complete connected graph
 g.add_vertices("A")