array(5) {
  ["pa_color"]=>
  object(WC_Product_Attribute)#39668 (1) {
    ["data":protected]=>
    array(6) {
      ["id"]=>
      int(3)
      ["name"]=>
      string(8) "pa_color"
      ["options"]=>
      array(1) {
        [0]=>
        int(74)
      }
      ["position"]=>
      int(0)
      ["visible"]=>
      bool(true)
      ["variation"]=>
      bool(true)
    }
  }
  ["pa_marca"]=>
  object(WC_Product_Attribute)#39896 (1) {
    ["data":protected]=>
    array(6) {
      ["id"]=>
      int(4)
      ["name"]=>
      string(8) "pa_marca"
      ["options"]=>
      array(1) {
        [0]=>
        int(79)
      }
      ["position"]=>
      int(1)
      ["visible"]=>
      bool(true)
      ["variation"]=>
      bool(true)
    }
  }
  ["pa_materiales"]=>
  object(WC_Product_Attribute)#39909 (1) {
    ["data":protected]=>
    array(6) {
      ["id"]=>
      int(1)
      ["name"]=>
      string(13) "pa_materiales"
      ["options"]=>
      array(1) {
        [0]=>
        int(63)
      }
      ["position"]=>
      int(2)
      ["visible"]=>
      bool(true)
      ["variation"]=>
      bool(true)
    }
  }
  ["pa_temperatura-recomenda"]=>
  object(WC_Product_Attribute)#39913 (1) {
    ["data":protected]=>
    array(6) {
      ["id"]=>
      int(7)
      ["name"]=>
      string(24) "pa_temperatura-recomenda"
      ["options"]=>
      array(1) {
        [0]=>
        int(89)
      }
      ["position"]=>
      int(3)
      ["visible"]=>
      bool(true)
      ["variation"]=>
      bool(true)
    }
  }
  ["tamano-largo-cm-ancho-cm-alto-cm"]=>
  object(WC_Product_Attribute)#39893 (1) {
    ["data":protected]=>
    array(6) {
      ["id"]=>
      int(0)
      ["name"]=>
      string(37) "Tamaño (Largo cm, Ancho cm, Alto cm)"
      ["options"]=>
      array(1) {
        [0]=>
        string(11) "19x11.5x6.4"
      }
      ["position"]=>
      int(4)
      ["visible"]=>
      bool(true)
      ["variation"]=>
      bool(true)
    }
  }
}

-----NULL

xxxxstring(8) "pa_color" bool(true)

xxxxstring(8) "pa_marca" bool(true)

xxxxstring(13) "pa_materiales" bool(true)

xxxxstring(24) "pa_temperatura-recomenda" bool(true)

xxxxstring(37) "Tamaño (Largo cm, Ancho cm, Alto cm)" bool(false)