Element weight

weight =>

array:10 [
  "class" => "Drupal\Core\Render\Element\Weight"
  "provider" => "core"
  "id" => "weight"
  "#input" => true
  "#delta" => 10
  "#default_value" => 0
  "#process" => array:2 [
    0 => array:2 [
      0 => "Drupal\Core\Render\Element\Weight"
      1 => "processWeight"
    ]
    1 => array:2 [
      0 => "Drupal\Core\Render\Element\Weight"
      1 => "processAjaxForm"
    ]
  ]
  "#value_callback" => array:2 [
    0 => "Drupal\Core\Render\Element\Weight"
    1 => "valueCallback"
  ]
  "#type" => "weight"
  "#defaults_loaded" => true
]