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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_subassistants(self):
 """Return list of instantiated subassistants. Usually, this needs not be overriden in subclasses, you should just override get_subassistant_classes Returns: list of instantiated subassistants """

        if not hasattr(self, '_subassistants'):
            self._subassistants = []
            # we want to know, if type(self) defines 'get_subassistant_classes',
            # we don't want to inherit it from superclass (would cause recursion)
            if 'get_subassistant_classes' in vars(type(self)):
                for a in self.get_subassistant_classes():
                    self._subassistants.append(a())
        return self._subassistants