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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 lookup_bulk(self, ResponseGroup="Large", **kwargs):
 """Lookup Amazon Products in bulk. Returns all products matching requested ASINs, ignoring invalid entries. :return: A list of :class:`~.AmazonProduct` instances. """

        response = self.api.ItemLookup(ResponseGroup=ResponseGroup, **kwargs)
        root = objectify.fromstring(response)
        if not hasattr(root.Items, 'Item'):
            return []
        return list(
            AmazonProduct(
                item,
                self.aws_associate_tag,
                self,
                region=self.region) for item in root.Items.Item
        )