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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 _assign(self, values):
 """Assign the values passed as either a dict or list to the object if the key for each value matches an available attribute on the object. :param dict values: The values to assign """

        LOGGER.debug('Assigning values: %r', values)
        if not values:
            return
        keys = self.keys()
        if not self._ref:
            keys.append('_ref')
        if isinstance(values, dict):
            for key in keys:
                if values.get(key):
                    if isinstance(values.get(key), list):
                        items = list()
                        for item in values[key]:
                            if isinstance(item, dict):
                                if '_ref' in item:
                                    obj_class = get_class(item['_ref'])
                                    if obj_class:
                                        items.append(obj_class(self._session,
                                                               **item))
                            else:
                                items.append(item)
                        setattr(self, key, items)
                    else:
                        setattr(self, key, values[key])
        elif isinstance(values, list):
            self._assign(values[0])
        else:
            LOGGER.critical('Unhandled return type: %r', values)