Odd Even Linked List LeetCode solution in Python

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class Solution:
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    def oddEvenList(self, head: Optional[ListNode]) -> Optional[ListNode]:
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        if head is None:
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            return
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        odd, even_start, even = head, head.next, head.next
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        while odd is not None and even is not None:
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            odd.next = even.next
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            if odd.next is not None:
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                odd = odd.next
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                even.next = odd.next
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                even = even.next
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            else:
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                break
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        odd.next = even_start
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        return head