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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 sql(self):
 """If you access this attribute, we will build an SQLite database out of the FASTA file and you will be able access everything in an indexed fashion, and use the blaze library via sql.frame"""

        from fasta.indexed import DatabaseFASTA, fasta_to_sql
        db = DatabaseFASTA(self.prefix_path + ".db")
        if not db.exists: fasta_to_sql(self.path, db.path)
        return db