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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 add_rec_new(self, k, val):
 """Recursively add a new value and its children to me, and assign a variable to it. Args: k (str):
 The name of the variable to assign. val (LispVal):
 The value to be added and assigned. Returns: LispVal: The added value. """

        self.rec_new(val)
        self[k] = val
        return val