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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(self, entry_id, new_label):
 """ Updates an entry with entry_id with the given label Parameters entry_id : int entry id of the sample to update. label : {int, None} Label of the sample to be update. """

        self.data[entry_id] = (self.data[entry_id][0], new_label)
        self.modified = True
        for callback in self._update_callback:
            callback(entry_id, new_label)