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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 reference_fasta(self):
 """Absolute path to the fasta file with EricScript reference data."""

        if self._db_location:
            ref_files = glob.glob(os.path.join(self._db_location, "*", self._REF_FASTA))
            if ref_files:
                return ref_files[0]