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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 get_pair(self, term1, term2):
 """ Get the value for a pair of terms. Args: term1 (str) term2 (str) Returns: The stored value. """


        key = self.key(term1, term2)
        return self.pairs.get(key, None)