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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 ground_height(self):
        '''return height above ground in feet'''
        lat = self.pkt['I105']['Lat']['val']
        lon = self.pkt['I105']['Lon']['val']
        global ElevationMap
        ret = ElevationMap.GetElevation(lat, lon)
        ret -= gen_settings.wgs84_to_AMSL
        return ret * 3.2807