ryu ImportError: No module named ryu.cmd.manager

[root@kunpeng82 Ryu-SDN-IP]#  ./bin/sdnip-mgr --sdn-ip-cfg-file ./config.json  --observe-links sdnip.arp_proxy sdnip.fwd_bgp sdnip.sdn_ip
Traceback (most recent call last):
  File "./bin/sdnip-mgr", line 3, in <module>
    from ryu.cmd.manager import main
ImportError: No module named ryu.cmd.manager
[root@kunpeng82 Ryu-SDN-IP]#

[root@kunpeng82 Ryu-SDN-IP]# pip list | grep ryu
DEPRECATION: Python 2.7 reached the end of its life on January 1st, 2020. Please upgrade your Python as Python 2.7 is no longer maintained. pip 21.0 will drop support for Python 2.7 in January 2021. More details about Python 2 support in pip, can be found at https://pip.pypa.io/en/latest/development/release-process/#python-2-support
[root@kunpeng82 Ryu-SDN-IP]# pip3 list | grep ryu       ---装了
DEPRECATION: The default format will switch to columns in the future. You can use --format=(legacy|columns) (or define a format=(legacy|columns) in your pip.conf under the [list] section) to disable this warning.
ryu (4.34)
[root@kunpeng82 Ryu-SDN-IP]#

#!/usr/bin/env python                ------------改成python3

from ryu.cmd.manager import main
from sdnip import conf_mgr, arp_proxy


main()