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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 delete(self, p_timestamp=None, p_write=True):
 """ Removes backup from the backup file. """

        timestamp = p_timestamp or self.timestamp
        index = self._get_index()

        try:
            del self.backup_dict[timestamp]
            index.remove(index[[change[0] for change in index].index(timestamp)])
            self._save_index(index)

            if p_write:
                self._write()
        except KeyError:
            pass