Copy List with Random Pointer LeetCode solution in Python

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from collections import defaultdict
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"""
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# Definition for a Node.
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class Node:
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    def __init__(self, x: int, next: 'Node' = None, random: 'Node' = None):
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        self.val = int(x)
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        self.next = next
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        self.random = random
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"""
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class Solution:
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    def copyRandomList(self, head: "Optional[Node]") -> "Optional[Node]":
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        # ll=res
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        # k=0
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        # ind=0
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        # kmk=1
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        jj = None
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        g = defaultdict(lambda: -1)
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        k = 0
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        hh = head
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        while head:
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            res = Node(head.val)
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            if k == 0:
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                jj = res
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            if k == 1:
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                prev.next = res
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            g[head] = res
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            prev = res
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            k = 1
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            head = head.next
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        # print(g)
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        # for i in g:
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        #     print(i.val,g[i].val)
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        kk = jj
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        mm = jj
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        # print(head)
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        while hh:
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            if hh.random != None:
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                jj.random = g[hh.random]
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            else:
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                jj.random = None
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            hh = hh.next
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            jj = jj.next
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            # head=head.next
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        kkk = kk
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        # while(kk):
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        #     print(kk.val)
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        #     kk=kk.next
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        return kkk
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#             if g[ind]!=-1:
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#                 g[ind].random=res
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#             res=Node(head.val)
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#             if kmk==1:
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#                 ll=res
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#             kmk=0
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#             mm=head.next
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#             if mm:
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#                 jk=Node(mm.val)
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#                 res.next=jk
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#             if head.random !=None:
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#                 g[head.random]=res
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#             else:
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#                 res.random=None
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#             head=head.next
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#             ind+=1
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#             # res=res.next
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#         return ll
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# if k==0:
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#     res.val=head.val
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#     mm=head.next