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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 resolution(self):
 """ Get the tile resolution at the current position. The scale in WG84 depends on * the zoom level (obviously) * the latitude * the tile size References: * http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Resolution_and_Scale * http://gis.stackexchange.com/questions/7430/what-ratio-scales-do-google-maps-zoom-levels-correspond-to Returns: float: meters per pixel """

        geo_coords = self.to_geographic()
        resolution = abs(_initialresolution * math.cos(geo_coords.lat * _pi_180) / (2**self.zoom))
        return resolution