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  $product_types = [
    'fir_eva_control',
    'fir_eva_microphones',
    'fir_eva_speakers',
  ];

  foreach ($product_types as $product_type) {
    $instance_info = field_info_instance('commerce_product', 'field_v_long_desc', $product_type);
    $instance_info['widget'] = [
      'type' => 'text_textarea',
      'settings' => [
        'rows' => 5,
      ],
      'weight' => 5,
    ];
    $instance_info['settings']['text_processing'] = 0;
    field_update_instance($instance_info);
  }