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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 _is_at_ref_end(self, nucmer_hit):
        '''Returns True iff the hit is "close enough" to the end of the reference sequence'''
        hit_coords = nucmer_hit.ref_coords()
        return hit_coords.end >= nucmer_hit.ref_length - self.ref_end_tolerance