Variable default_bundle in migration? Field collection to varying paragraph types I'm trying to migrate a D7 field collection to D8 paragraphs, but to a different paragraph bundle type depending on the value in one of the field collection's fields. 

The logic is as follows: If the field collection's field_type value is "header", the migration should create a header paragraph type. If the field collection's field_type value is "card" it should migrate to a card paragraph type.

I'm trying to set a variable in process, and assign the value of that variable to default_bundle in the destination, but it's not working, the paragraph type is empty for the entities created by this migration:

langcode: en
status: true
dependencies: { }
id: d7_field_collection_list_items 
class: null
field_plugin_method: null
cck_plugin_method: null
migration_tags:
 - 'Drupal 7'
migration_group: migrate_drupal_7
label: FC
source:
  plugin: d7_field_collection_item
  key: migrate
  field_name: field_list_item
process:    
  temp_bundle_type:
    plugin: static_map
    source: field_list_item_type
    map:            
      card: card
      header: header
    default_value: card 
destination:
  plugin: 'entity_reference_revisions:paragraph'
  default_bundle: '@temp_bundle_type'
migration_dependencies:
  required: { }
  optional: { }


What is the correct way to achieve what I am trying to do? I have tried several other methods without success.
Don't use the default_bundle at all, instead set the bundle type like other field values in the process section:

process:    
  temp_bundle_type:
    plugin: static_map
    source: field_list_item_type
    map:            
      card: card
      header: header
    default_value: card 
  type: '@temp_bundle_type'