I am trying to obtain class information on a field inside a model, when I only know name of the field and name of the model (both plain strings). How is it possible?
If you would like to see ALL fields on a Django model object you can simply introspect it by calling ._meta.get_fields() on the class (or an instantiated model object) to get at list of all fields. This API is current with the latest version of Django.
Example:
from django.contrib.auth.models import User
User._meta.get_fields()
This will return a tuple of all model fields. Documentation can be found HERE.