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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 remove(self, interval):
 """ Returns self after removing the interval and balancing. If interval is not present, raise ValueError. """

        # since this is a list, called methods can set this to [1],
        # making it true
        done = []
        return self.remove_interval_helper(interval, done, should_raise_error=True)