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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_all(self, callsign, timestamp=timestamp_now):
 """ Lookup a callsign and return all data available from the underlying database Args: callsign (str):
 Amateur Radio callsign timestamp (datetime, optional):
 datetime in UTC (tzinfo=pytz.UTC) Returns: dict: Dictionary containing the callsign specific data Raises: KeyError: Callsign could not be identified Example: The following code returns all available information from the country-files.com database for the callsign "DH1TW" { 'country': 'Fed. Rep. of Germany', 'adif': 230, 'continent': 'EU', 'latitude': 51.0, 'longitude': -10.0, 'cqz': 14, 'ituz': 28 } Note: The content of the returned data depends entirely on the injected :py:class:`LookupLib` (and the used database). While the country-files.com provides for example the ITU Zone, Clublog doesn't. Consequently, the item "ituz" would be missing with Clublog (API or XML) :py:class:`LookupLib`. """

        callsign_data = self._lookup_callsign(callsign, timestamp)

        try:
            cqz = self._lookuplib.lookup_zone_exception(callsign, timestamp)
            callsign_data[const.CQZ] = cqz
        except KeyError:
            pass

        return callsign_data