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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 _getDone(self, done, undone):
 """Parses the done|undone state. :done: Done marking pattern. :undone: Not done marking pattern. :returns: Pattern for done|undone or None if neither were specified. """

        if done:
            return self._getPattern(done, True)
        if undone:
            return self._getPattern(undone, False)