PLATZI / 403 FORBIDDEN

[Argentum72]

Checklist

• [x] I'm reporting a broken site support issue
• [x] I've verified that I'm running youtube-dl version 2020.01.15
• [x] I've checked that all provided URLs are alive and playable in a browser
• [x] I've checked that all URLs and arguments with special characters are properly quoted or escaped
• [x] I've searched the bugtracker for similar bug reports including closed ones
• [x] I've read bugs section in FAQ

Verbose log

youtube-dl.exe  -u **USER** -p **PASS** -v https://platzi.com/clases/**COURSES**
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: ['-u', 'PRIVATE', '-p', 'PRIVATE', '-v', 'https://platzi.com/clases/1638-api-rest/21612-introduccion-y-bienveni-3']
[debug] Encodings: locale cp1252, fs mbcs, out cp850, pref cp1252
[debug] youtube-dl version 2020.01.15
[debug] Python version 3.4.4 (CPython) - Windows-10-10.0.18362
[debug] exe versions: none
[debug] Proxy map: {}
[Platzi] Downloading login page
[Platzi] Logging in
ERROR: Unable to download webpage: HTTP Error 403: Forbidden (caused by HTTPError()); please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; type  youtube-dl -U  to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\ytdl-org\tmp43n_zyg3\build\youtube_dl\extractor\common.py", line 627, in _request_webpage
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\ytdl-org\tmp43n_zyg3\build\youtube_dl\YoutubeDL.py", line 2237, in urlopen
  File "C:\Python\Python34\lib\urllib\request.py", line 470, in open
  File "C:\Python\Python34\lib\urllib\request.py", line 580, in http_response
  File "C:\Python\Python34\lib\urllib\request.py", line 508, in error
  File "C:\Python\Python34\lib\urllib\request.py", line 442, in _call_chain
  File "C:\Python\Python34\lib\urllib\request.py", line 588, in http_error_default

## Description

I was doing the same thing I did 3 days ago to download the classes and now it doesn't work.
I tried other course links : new and already downloaded and it still doesn't work. Are there any parameters missing from the command line? Or has the site improved security? 

[EParedez]

I was checking this problem, is caused for the login page is not loaded correctly, this can check if you use postman to load the login page (https://platzi.com/login/)

We notice raised an error 403 Forbidden

[dirkf]

I've updated the PR code. Please test and follow up there.