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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 inverse_mercator(xy):
 """ Given coordinates in spherical mercator, return a lon,lat tuple. """

    lon = (xy[0] / 20037508.34) * 180
    lat = (xy[1] / 20037508.34) * 180
    lat = 180 / math.pi * \
        (2 * math.atan(math.exp(lat * math.pi / 180)) - math.pi / 2)
    return (lon, lat)