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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 _update_access_key_pair(self, access_key_id, key, val):
 """ Helper for updating access keys in a DRY fashion. """

        # Get current state via HTTPS.
        current_access_key = self.get_access_key(access_key_id)

        # Copy and only change the single parameter.
        payload_dict = KeenApi._build_access_key_dict(current_access_key)
        payload_dict[key] = val

        # Now just treat it like a full update.
        return self.update_access_key_full(access_key_id, **payload_dict)