def from_content_type(self, content_type, content_encoding=None):
        """Return the most appropriate Response class from an HTTP Content-Type
        header """
        if content_encoding:
            return Response
        mimetype = to_native_str(content_type).split(';')[0].strip().lower()
        return self.from_mimetype(mimetype)
Return the most appropriate Response class from an HTTP Content-Type
        header 
stackoverflow/venv/lib/python3.6/site-packages/scrapy/responsetypes.py