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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 close(self):
 """Flush data, write 28 bytes BGZF EOF marker, and close BGZF file. samtools will look for a magic EOF marker, just a 28 byte empty BGZF block, and if it is missing warns the BAM file may be truncated. In addition to samtools writing this block, so too does bgzip - so this implementation does too. """

        if self._buffer:
            self.flush()
        self._handle.write(_bgzf_eof)
        self._handle.flush()
        self._handle.close()