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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 next(self, reward, ask_id, lbl):
 """Taking the label and the reward value of last question and returns the next question to ask."""

        # first run don't have reward, TODO exception on reward == -1 only once
        if reward == -1:
            return next(self.exp4p_gen)
        else:
            # TODO exception on reward in [0, 1]
            return self.exp4p_gen.send((reward, ask_id, lbl))