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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 _make_index(self, fasta, index):
 """ Index a single, one-sequence fasta-file"""

        out = open(index, "wb")
        f = open(fasta)
        # Skip first line of fasta-file
        line = f.readline()
        offset = f.tell()
        line = f.readline()
        while line:
            out.write(pack(self.pack_char, offset))
            offset = f.tell()
            line = f.readline()
        f.close()
        out.close()