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

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data_structures/heap/fibonacci_heap.py

@@ -12,6 +12,7 @@ Operations supported:
 - Merge: O(1)
 """
 
+
 class Node:
     """
     A node in a Fibonacci heap.
@@ -28,6 +29,7 @@ class Node:
         degree: Number of children.
         mark: Boolean indicating if node has lost a child.
     """
+
     def __init__(self, val):
         self.val = val
         self.parent = None
@@ -324,8 +326,7 @@ class FibonacciHeap:
             node: Starting node for cascading cut.
         """
 
-        parent = node.parent
-        if parent:
+        if parent := node.parent:
             if not node.mark:
                 node.mark = True
             else:
@@ -359,4 +360,5 @@ class FibonacciHeap:
 
 if __name__ == "__main__":
     import doctest
+
     doctest.testmod()