···4455from scrapy.exceptions import DropItem
6677+class RemoveNonePipeline(object):
88+99+ def __init__(self):
1010+ self.known_values = set()
1111+1212+ def process_item(self, item, spider):
1313+ """
1414+ Processing the items so None values are replaced by empty strings
1515+ :param item: The incoming item
1616+ :param spider: The spider which scraped the spider
1717+ :return: :raise DropItem: Returns the item if unique or drops them if it's already known
1818+ """
1919+ for key in item:
2020+ if item[key] is None:
2121+ item[key] = ""
2222+ return item
723824class DuplicatePipeline(object):
925