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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_data(self, data_key, key=''):
 """Get the data from the cache. :param data_key: a key for accessing the data; :param key: if provided (e.g. non-empty string), will be used to decrypt the data as a password; :returns: the data extracted from the cache, a python object. """


        flag = False  # set to True if data was successfully extracted.
        extracted = self.get(data_key, -1)

        if extracted != -1:
            try:
                data, expired, noc, ncalls = self._from_bytes(extracted, key=key)
                flag = True
            except ValueError:
                return None, flag

            if noc:
                ncalls += 1
                self[data_key] = self._to_bytes(data, expired=expired,
                                                key=key, noc=noc,
                                                ncalls=ncalls)
                if ncalls >= noc:
                    self.remove(data_key)
                    flag = False

            if expired and datetime.datetime.now() > expired:
                self.remove(data_key)
                flag = False

        return (data, flag) if flag else (None, flag)