<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def _username():
    '''
    Grain for the minion username
    '''
    if pwd:
        username = pwd.getpwuid(os.getuid()).pw_name
    else:
        username = getpass.getuser()

    return username