Design Browser History LeetCode solution in Python

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# Runtime: 702 ms (Top 9.12%) | Memory: 16.8 MB (Top 36.03%)
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class Node:
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    def __init__(self, val):
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        self.val = val
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        self.prev = None
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        self.next = None
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class BrowserHistory:
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    def __init__(self, web):
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        self.Node = Node(web)
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        self.ptr = self.Node
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    def visit(self, web):
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        self.newWeb = Node(web)
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        self.newWeb.prev = self.ptr
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        self.ptr.next = self.newWeb
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        self.ptr = self.ptr.next
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    def back(self, steps):
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        i = 0
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        while i < steps:
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            if self.ptr.prev:
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                self.ptr = self.ptr.prev
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            else:
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                break
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            i += 1
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        return self.ptr.val
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    def forward(self, steps):
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        i = 0
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        while i < steps:
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            if self.ptr.next:
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                self.ptr = self.ptr.next
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            else:
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                break
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            i += 1
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        return self.ptr.val