pip install uwsgi - python3_plugin.so no found

gistfile1.txt

# Install System-wide
sudo apt install -y uwsgi-core uwsgi-plugin-python3

# Run system uwsgi: this works!
$ cd ~/myproject
$ uwsgi --ini production.ini 
[uWSGI] getting INI configuration from production.ini


# Install uwsgi via pip
# (A virtual environment is set up in "env/")
cd ~/myproject
env/bin/python3 -m pip install uwsgi

# Run pip-installed uwsgi: 
$ env/bin/uwsgi --ini production.ini 
[uWSGI] getting INI configuration from production.ini
open("./python3_plugin.so"): No such file or directory [core/utils.c line 3721]
!!! UNABLE to load uWSGI plugin: ./python3_plugin.so: cannot open shared object file: No such file or directory !!!

thx~