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class Solution:
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    def isSubtree(self, root: Optional[TreeNode], subRoot: Optional[TreeNode]) -> bool:
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        if subRoot == None:
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            return True
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        if root == None:
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            return False
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        sameTree = self.isSameTree(root, subRoot)
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        subTreeOnLeft = self.isSubtree(root.left, subRoot)
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        subTreeOnRight = self.isSubtree(root.right, subRoot)
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        return subTreeOnLeft or subTreeOnRight or sameTree
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    def isSameTree(self, root: Optional[TreeNode], subRoot: Optional[TreeNode]) -> bool:
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        if root == None and subRoot == None:
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            return True
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        if root == None or subRoot == None:
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            return False
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        if root.val != subRoot.val:
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            return False
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        return self.isSameTree(root.left, subRoot.left) and self.isSameTree(
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            root.right, subRoot.right
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        )