Perhaps you're a budding pentester. You come across a login page. You could try brute forcing it. Or, you could try injecting it. Doing it manually could take a while. Why not use Python and a wordlist do that part for you?
Here's a video where I show you how to do it.
Ps. Learn how to use the requests module in Python.
Repo with the script I used:
And here's the OWASP Juice Shop on TryHackMe !