Delete the Middle Node of a Linked List LeetCode solution in Python

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# Runtime: 2948 ms (Top 45.50%) | Memory: 60.7 MB (Top 40.45%)
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# Definition for singly-linked list.
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# class ListNode:
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# def __init__(self, val=0, next=None):
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# self.val = val
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# self.next = next
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class Solution:
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    def deleteMiddle(self, head: Optional[ListNode]) -> Optional[ListNode]:
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        if not head:
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            return head
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        if head and not head.next:
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            return None
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        prev = ListNode(0, head)
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        slow = fast = head
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        while fast and fast.next:
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            prev = slow
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            slow = slow.next
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            fast = fast.next.next
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        prev.next = slow.next
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        return head