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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 _run(self, strategy, parameters=None):
        '''
        Run single trial of MAB strategy.

        Parameters
        ----------
        strategy : function
        parameters : dict

        Returns
        -------
        None
        '''

        choice = self.run_strategy(strategy, parameters)
        self.choices.append(choice)
        payout = self.bandits.pull(choice)
        if payout is None:
            print('Trials exhausted. No more values for bandit', choice)
            return None
        else:
            self.wins[choice] += payout
        self.pulls[choice] += 1