name and password for pgadmin4

I installed phadmin4 Python version on Windows 10 machine:
python3.exe -m pip install pgadmin4

Then started it for the first time:
pgadmin4
Starting pgAdmin 4. Please navigate to http://127.0.0.1:5050 in your browser.
* Serving Flask app "pgadmin" (lazy loading)
* Environment: production
   WARNING: Do not use the development server in a production environment.
   Use a production WSGI server instead.
* Debug mode: off

It did not ask for any name and password to set them up.

Which name and password is expected on the initial web page?