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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 convert_to_string(self, block):
 """Makes gene_block as str from list of SeqRecordExpanded objects of a gene_code. Override this function if the dataset block needs to be different due to file format. This block will need to be split further if the dataset is FASTA or TNT and the partitioning scheme is 1st-2nd, 3rd. As the dataset is split into several blocks due to 1st-2nd, 3rd we cannot translate to aminoacids or degenerate the sequences. """

        if self.partitioning != '1st-2nd, 3rd':
            return self.make_datablock_by_gene(block)
        else:
            if self.format == 'FASTA':
                return self.make_datablock_considering_codon_positions_as_fasta_format(block)
            else:
                return self.make_datablock_by_gene(block)