Pull features from the instream and write them to the output.

def write(self):
        """Pull features from the instream and write them to the output."""
        for entry in self._instream:
            if isinstance(entry, Feature):
                for feature in entry:
                    if feature.num_children > 0 or feature.is_multi:
                        if feature.is_multi and feature != feature.multi_rep:
                            continue
                        self.feature_counts[feature.type] += 1
                        fid = '{}{}'.format(feature.type,
                                            self.feature_counts[feature.type])
                        feature.add_attribute('ID', fid)
                    else:
                        feature.drop_attribute('ID')
            if isinstance(entry, Sequence) and not self._seq_written:
                print('##FASTA', file=self.outfile)
                self._seq_written = True
            print(repr(entry), file=self.outfile)