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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 process_shells(self, shells):
 """Processing a list of shells."""

        result = {'success': True, 'output': []}
        if self.parallel and len(shells) > 1:
            result = self.process_shells_parallel(shells)
        elif len(shells) > 0:
            result = self.process_shells_ordered(shells)
        return result