python源码：
    conn = imaplib.IMAP4("imap.qiye., 143)
    conn.login("***@, "*******")
    print conn.list()
    conn.select(email_file)
    _t, _data = conn.search(None, 'ALL')

报错：error message: command SEARCH illegal in state AUTH, only allowed in states SELECTED

求原因？求解法？