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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 genome(self):
 """ "genome" dictionary ready for pybedtools, based on the BAM header. """

        # This gets the underlying pysam Samfile object
        f = self.adapter.fileobj
        d = {}
        for ref, length in zip(f.references, f.lengths):
            d[ref] = (0, length)
        return d