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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 execute(self, *args):
 """ Pass one command to exiftool and return a deferred which is fired as soon as the command completes. @param *args: Command line arguments passed to exiftool @type *args: C{unicode} @rtype: C{Deferred} @return: A deferred whose callback will be invoked when the command completed. """


        result = defer.Deferred()
        if self.connected and not self._stopped:
            self._tag += 1

            args = tuple(args) + ('-execute{:d}'.format(self._tag), '')
            safe_args = [fsencode(arg) for arg in args]
            self.transport.write(b'\n'.join(safe_args))

            result = defer.Deferred()
            self._queue[self._tag] = result
        else:
            result.errback(error.ConnectionClosed('Not connected to exiftool'))

        return result