Dashboard get_nodes issue. Am I missing something?

[Uma]

I am reading through the code for dashboard and am a bit puzzled

https://github.com/django-oscar/django-oscar/blob/master/src/oscar/apps/dashboard/nav.py

https://github.com/django-oscar/django-oscar/blob/master/src/oscar/apps/dashboard/menu.py

looking at the menu.py get_nodes gets node objs via create_menu funtion which creates node obj

and ensure parent and children are linked together

but what puzzles me that when in get_nodes function

there is a for loop which gets each function and runs it through filter and this filter method is defined in nav.py

this function checks if the nav is visible for user if it is, it creates the Node object again

not sure why if the Node obj is already created for create_menu why go through filter method to create it again

I understand it needs to check the visibility for the user but shouldn't it leave it at that

I am missing something here can someone shed some light on it please

Thanks,

U