def get(self, key, default=None):
        "Returns the default value if the requested data doesn't exist"
        try:
            val = self[key]
        except KeyError:
            return default
        if val == []:
            return default
        return val
Returns the default value if the requested data doesn't exist
stackoverflow/venv/lib/python3.6/site-packages/scrapy/utils/datatypes.py