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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 create_fa(self):
 """Create a FASTA file with extracted sequences. 		"""


        if self._seqs is None:
            os.symlink(self._fa0_fn, self._fa_fn)
        else:
            in_seqs = pyfaidx.Fasta(self._fa0_fn)

            with open(self._fa_fn, "w+") as g:
                for seq_desc in self._seqs:
                    x = in_seqs[seq_desc]
                    name, seq = x.name, str(x)
                    g.write(">" + name + "\n")
                    n = 80
                    seq_split = "\n".join([seq[i:i + n] for i in range(0, len(seq), n)])
                    g.write(seq_split + "\n")