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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 distance_from(self, lat, lon):
        '''get distance from a point'''
        lat1 = self.pkt['I105']['Lat']['val']
        lon1 = self.pkt['I105']['Lon']['val']
        return mp_util.gps_distance(lat1, lon1, lat, lon)