Django: best way to convert data from model to view
If you are using Django Rest Framework, then you can simply use serializers. But I don't think that is a case. What you want to accomplish seems very similar to the role of django forms, but as such they are only used (conventionally) for saving/updating models i.e. POST requests. Now either you can define a new class for filtering/rendering and use that in your view or just go ahead and use django forms which would automatically provide basic cleaning for different fields.
My django app displays the objects from database in table view. The problem is that these objects (models) are pretty complex: the have 50+ fields. Nearly for each field I have to do some formatting:

conver phone numbers from int 71234567689 to "+7 (123) 456789"
display long prices with spaces: "7 000 000" instead of "7000000"
construct full address from several fields like "street", "house" and so on (logic if pretty complex with several if-else-s)
and so on

Django templating language has several useful tags for simple cases but I guess is not suitable in general case (like mine) for serious formatting.
Create the @property-s in model class is also not an option because the question is about rendering and is not related to model.
So I guess I should do my conversions in view: create dict for each obj, fill with converted data and pass to template. 
But! The model has a lot of fields and I don't want to copy them all :) Moreover, it would be great to preserve model structure to use it in django template (say, regroup) and query set laziness.
So the greatest way would be to instruct django "how to render". Is it possible?