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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 filter_record(self, record):
 """ Filter a record, truncating or dropping at an 'N' """

        nloc = record.seq.find('N')
        if nloc == -1:
            return record
        elif self.action == 'truncate':
            return record[:nloc]
        elif self.action == 'drop':
            raise FailedFilter()
        else:
            assert False