Failed to install PYNQ

Hello, everyone

I am new to use PYNQ and I follow the instruction from GitHub - Xilinx/PYNQ: Python Productivity for ZYNQ
When I used the command, sudo pip3 install --upgrade --upgrade-strategy only-if-needed pynq, I encountered an error.

ERROR: Command errored out with exit status 1:
command: /usr/bin/python3 -c ‘import sys, setuptools, tokenize; sys.argv[0] = ‘"’"’/tmp/pip-install-5b2owj6a/pynq/’"’"’; file=’"’"’/tmp/pip-install-5b2owj6a/pynq/’"’"’;f=getattr(tokenize, ‘"’"‘open’"’"’, open)(file);’"’"’\r\n’"’"’, ‘"’"’\n’"’"’);f.close();exec(compile(code, file, ‘"’"‘exec’"’"’))’ egg_info --egg-base /tmp/pip-install-5b2owj6a/pynq/pip-egg-info
cwd: /tmp/pip-install-5b2owj6a/pynq/
Complete output (9 lines):
Traceback (most recent call last):
File “”, line 1, in
File “/tmp/pip-install-5b2owj6a/pynq/”, line 46, in
from pynq.utils import download_overlays
File “/tmp/pip-install-5b2owj6a/pynq/pynq/”, line 33, in
from .xlnk import Xlnk
File “/tmp/pip-install-5b2owj6a/pynq/pynq/”, line 38, in
import cffi
ModuleNotFoundError: No module named ‘cffi’
ERROR: Command errored out with exit status 1: python egg_info Check the logs for full command output.

Could someone help me?
Thanks a lot!

What board are you using?
The command assumes you have an existing image running. If you are new, you would be better just using one of the pre-compiled images and making a new SD card image.