A working D7 to D8 node migration

source:
  plugin: d7_node
  node_type: market_center
  key: d7finra
  constants:
    uid_root: 1
    node_article: 'article'
destination:
  plugin: entity:node
process:
  # Hardcode the destination node type (bundle) as 'migrate_example_beer'.
  id: nid
  type:
    plugin: default_value
    default_value: article
  title: title
  field_mm_mcid: field_mm_mcid
  field_mm_url:
    plugin: iterator
    source: field_mm_url
    process:
      uri: url
      title: title
      options: attributes
  field_core_content_type_tax:
    plugin: sub_process
    source: field_core_content_type_tax
    process:
      target_id: tid
  field_mm_comments:
    plugin: iterator
    source: field_mm_comments
    process:
      value: value
      format: full_html
  field_mm_internal_notes:
    plugin: iterator
    source: field_mm_internal_notes
    process:
      value: value
      format: full_html
migration_dependencies: {}