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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 pull(self, arm_id, success, failure):
        '''
        Pull arms.

        Args:
            arm_id:     Arms master id.
            success:    The number of success.
            failure:    The number of failure.
        '''
        self.__beta_dist_dict[arm_id].observe(success, failure)