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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 index(self, overwrite=False):
 """ Assuming that all necessary data for this Genome has been downloaded, generate the GTF database and save efficient representation of FASTA sequence files. """

        if self.requires_gtf:
            self.db.connect_or_create(overwrite=overwrite)
        if self.requires_transcript_fasta:
            self.transcript_sequences.index(overwrite=overwrite)
        if self.requires_protein_fasta:
            self.protein_sequences.index(overwrite=overwrite)