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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 get_aircraft(self):
 """all aircraft that are stored in memeory"""

        acs = self.acs
        icaos = list(acs.keys())
        for icao in icaos:
            if acs[icao]['lat'] is None:
                acs.pop(icao)
        return acs