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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 write_reg(self, filename):
 """ Write a ds9 region file that represents this region as a set of diamonds. Parameters filename : str File to write """

        with open(filename, 'w') as out:
            for d in range(1, self.maxdepth+1):
                for p in self.pixeldict[d]:
                    line = "fk5; polygon("
                    # the following int() gets around some problems with np.int64 that exist prior to numpy v 1.8.1
                    vectors = list(zip(*hp.boundaries(2**d, int(p), step=1, nest=True)))
                    positions = []
                    for sky in self.vec2sky(np.array(vectors), degrees=True):
                        ra, dec = sky
                        pos = SkyCoord(ra/15, dec, unit=(u.degree, u.degree))
                        positions.append(pos.ra.to_string(sep=':', precision=2))
                        positions.append(pos.dec.to_string(sep=':', precision=2))
                    line += ','.join(positions)
                    line += ")"
                    print(line, file=out)
        return