Django & WSGI - permission denied - django

Question

I have a config like this :
CentOS 7 - Varnish ( cache server ) / Nginx ( reverse proxy ) / Apache
And it's my Django configuration :
WSGISocketPrefix /var/run/wsgi
<VirtualHost ip:8181>
ServerName domain.ir
ServerAlias www.domain.ir
ServerAdmin info#domain.ir
DocumentRoot /var/www/DjangoProject
UseCanonicalName On
ScriptAlias /cgi-bin/ /var/www/DjangoProject/cgi-bin/
<Directory /var/www/DjangoProject/DjangoProject>
<Files wsgi.py>
Require all granted
</Files>
</Directory>
Alias /statics/ "/var/www/DjangoProject/statics/"
<Directory "/var/www/DjangoProject/statics">
Require all granted
</Directory>
WSGIDaemonProcess DjangoProject python-path=/usr/lib/python3.4/site-packages python-home=/var/www/DjangoProject user=djangouser socket-user=djangouser
WSGIProcessGroup DjangoProject
WSGIApplicationGroup %{GLOBAL}
WSGIScriptAlias / /var/www/DjangoProject/DjangoProject/wsgi.py
ErrorLog /var/log/apache/django-error.log
</VirtualHost>
When i want to open my website there is a permission denied error in apache log :
[wsgi:error] [pid 2131:tid 140344565954304] (13)Permission denied: [client 77.104.92.126:38982] mod_wsgi (pid=2131): Unable to connect to WSGI daemon process 'TiTar_API' on '/var/run/wsgi.2128.0.1.sock' as user with uid=99.
I know that uid=99 is nobody user. What's going on here? Why this user want to connect WSGI socket? What is the purpose of user and socket-user attributes in WSGIDaemonProcess?
Edit : I saw other questions too, but i think there is another problem ( nobody user )
Django-WSGI setup causing permission denied issues on CentOS 7
Django + Apache + mod_wsgi permission denied
https://serverfault.com/questions/357804/apache2-mod-wsgi-django-named-virtual-servers