code: def create_for_object(self, parent_object, slot, role='m', title=None):
          
          from .db import Placeholder
          parent_attrs = get_parent_lookup_kwargs(parent_object)
          obj = self.create(
              slot=slot,
              role=role or Placeholder.MAIN,
              title=title or slot.title().replace('_', ' '),
              **parent_attrs
          )
          obj.parent = parent_object  # fill the reverse cache
          return obj
docs: Create a placeholder with the given parameters