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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, key, value):
 """Insert a key-value pair in the list. The pair is inserted at the correct location so that the list remains sorted on *key*. If a pair with the same key is already in the list, then the pair is appended after all other pairs with that key. """

        self._find_lte(key)
        node = self._create_node(key, value)
        self._insert(node)