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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 pbf(self, bbox, geo_col=None, scale=4096):
 """Returns tranlated and scaled geometries suitable for Mapbox vector tiles. """

        col = geo_col or self.geo_field.name
        w, s, e, n = bbox.extent
        trans = self._trans_scale(col, -w, -s,
                                  scale / (e - w),
                                  scale / (n - s))
        g = AsText(trans)
        return self.annotate(pbf=g)