The getpass module provides two functions:
'Password: '. On Unix, the prompt is written to the file-like object stream, which defaults to
sys.stdout(this argument is ignored on Windows).
Availability: Macintosh, Unix, Windows. Changed in version 2.5: The stream parameter was added.
This function checks the environment variables LOGNAME, USER, LNAME and USERNAME, in order, and returns the value of the first one which is set to a non-empty string. If none are set, the login name from the password database is returned on systems which support the pwd module, otherwise, an exception is raised.