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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def insert(self, value):
 """Insert a value in the tree"""

        if not self.payload or value == self.payload:
            self.payload = value
        else:
            if value <= self.payload:
                if self.left:
                    self.left.insert(value)
                else:
                    self.left = BinaryTreeNode(value)
            else:
                if self.right:
                    self.right.insert(value)
                else:
                    self.right = BinaryTreeNode(value)