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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 compare(self):
 # pylint: disable=no-self-use """ Computes the difference between the candidate config and the running config. """

        # becuase we emulate the configuration history
        # the difference is between the last committed config and the running-config
        running_config = self._download_running_config()
        running_config_lines = running_config.splitlines()
        last_committed_config = self._last_working_config
        last_committed_config_lines = last_committed_config.splitlines()
        difference = difflib.unified_diff(running_config_lines, last_committed_config_lines, n=0)
        return '\n'.join(difference)