fixup! Format Python code with psf/black push

Author: github-actions

data_structures/linked_list/middle_element_of_linked_list.py

@@ -8,14 +8,14 @@ class LinkedList:
     def __init__(self):
         self.head = None
 
-    def push(self, new_data:int) -> int:
-        new_node = Node(new_data) 
-        new_node.next = self.head 
+    def push(self, new_data: int) -> int:
+        new_node = Node(new_data)
+        new_node.next = self.head
         self.head = new_node
         return self.head.data
 
     def middle_element(self) -> int:
-        '''
+        """
         >>> link = LinkedList()
         >>> link.middle_element()
         No element found.
@@ -44,11 +44,11 @@ def middle_element(self) -> int:
         >>> link.middle_element()
         12
         >>> 
-        '''
+        """
         slow_pointer = self.head
         fast_pointer = self.head
-        if self.head: 
-            while fast_pointer and fast_pointer.next: 
+        if self.head:
+            while fast_pointer and fast_pointer.next:
                 fast_pointer = fast_pointer.next.next
                 slow_pointer = slow_pointer.next
             return slow_pointer.data