When creating a Request object scrapy applies some url encoding methods. To revert these you can utilize a custom middleware and change the url to your needs.
You could use a Downloader Middleware like this:
class MyCustomDownloaderMiddleware(object):
def process_request(self, request, spider):
request._url = request.url.replace("%5B", "[", 2)
request._url = request.url.replace("%5D", "]", 2)
Don't forget to "activate" the middleware in settings.py like so:
DOWNLOADER_MIDDLEWARES = {
'so.middlewares.MyCustomDownloaderMiddleware': 900,
}
My project is named so and in the folder there is a file middlewares.py. You need to adjust those to your environment.