how can i get a user's password

I already use "core_user_get_users_by_field" function.

But I could no find user password in this result.

If anyone know, Please help me.

http://localhost:801/moodle2/webservice/rest/server.php?wstoken=f0ab480dfe2ff4a688a33244d918ff8a&wsfunction=core_user_get_users_by_field&moodlewsrestformat=json&field=email&values[]=aungzinphyo@innovix-solutions.com