How to place quote (' ') between Lesson 3 ?
Is that what you mean?
Anyway why would you want to to that for a url? Seems a bit weird.
If that is indeed what you need, I suggest reading up on some basics on quotes.
yes, that's what I mean.
I wonder why Lesson 3 does not appears on the website?
I except that it appears since, the success_url is the url it will brings after the file being successfully uploaded.
What are you doing with
'Lesson 3' ? If you inject this into a query without escaping, your query will fail.
A better url would be...
No quotes, no spaces. You can convert the GET class_name by replacing all - with spaces before using. Spaces and quotes in urls are weird like I stated. Better still store the resource as Lesson-3 (or Lesson3 or Lesson_3) in the first place