(user)
return user, (passwd if delim else None)
splitpasswd('user:passwd') -> 'user', 'passwd'.
splitpasswd('user:passwd') -> 'user', 'passwd'.
splitpasswd ( user : passwd ) - > user passwd .
def _splitpasswd(user):
    """splitpasswd('user:passwd') -> 'user', 'passwd'."""
    user, delim, passwd = user.partition(':')
    return user, (passwd if delim else None)
def _splitpasswd ( user ) : user , delim , passwd = user . partition ( ':' ) return user , ( passwd if delim else None )