I can’t understand the meaning of ‘%’ in the source code below. Questions have been recorded in the comments.
class RedirectView(View):
"""Provide a redirect on any GET request."""
permanent = False
url = None
pattern_name = None
query_string = False
def get_redirect_url(self, *args, **kwargs):
"""
Return the URL redirect to. Keyword arguments from the URL pattern
match generating the redirect request are provided as kwargs to this
method.
"""
if self.url:
url = self.url % kwargs # 1. what's the meaning of '%' here? a literal and a dict.
elif self.pattern_name:
url = reverse(self.pattern_name, args=args, kwargs=kwargs)
else:
return None
args = self.request.META.get('QUERY_STRING', '')
if args and self.query_string:
url = "%s?%s" % (url, args) # 2. And here, a literal string and a tuple
return url