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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_lat_long(self, callsign, timestamp=timestamp_now):
 """ Returns Latitude and Longitude for a callsign Args: callsign (str):
 Amateur Radio callsign timestamp (datetime, optional):
 datetime in UTC (tzinfo=pytz.UTC) Returns: dict: Containing Latitude and Longitude Raises: KeyError: No data found for callsign Example: The following code returns Latitude & Longitude for "DH1TW" { 'latitude': 51.0, 'longitude': -10.0 } Note: Unfortunately, in most cases the returned Latitude and Longitude are not very precise. Clublog and Country-files.com use the country's capital coordinates in most cases, if no dedicated entry in the database exists. Best results will be retrieved with QRZ.com Lookup. """

        callsign_data = self.get_all(callsign, timestamp=timestamp)
        return {
            const.LATITUDE: callsign_data[const.LATITUDE],
            const.LONGITUDE: callsign_data[const.LONGITUDE]
        }