Broken "Quick Start"

Going through the quick start tutorial here:
Documentation / Beginners Guide / Quick Start First Application

Under “adding character animations”, section 5, this code:

 @property({type: Animation})
 public BodyAnim: Animation|null = null;

Doesn’t work in CC 3.5.2 or 3.5.1.
“Body Anim” appears in the Inspector when Player is selected, but NO field appears, only “null” text and a “create” button.

Also, seeing this error:
[Window] Cannot convert undefined or null to objectTypeError: Cannot convert undefined or null to object
at Function.keys ()
at Object.update (C:\Cocos\CocosDashboard_1.2.0\resources.editors\Creator\3.5.1\resources\app.asar\builtin\scene\dist\contributions\ui-kit\ui-prop\types\object.ccc:1:469)
at Object.update (C:\Cocos\CocosDashboard_1.2.0\resources.editors\Creator\3.5.1\resources\app.asar\builtin\scene\dist\contributions\ui-kit\ui-prop\dump.ccc:1:3508)
at HTMLElement.render (C:\Cocos\CocosDashboard_1.2.0\resources.editors\Creator\3.5.1\resources\app.asar\node_modules@editor\creator\dist\ui-kit\renderer\components\prop\index.ccc:1:2082)
at C:\Cocos\CocosDashboard_1.2.0\resources.editors\Creator\3.5.1\resources\resources\3d\engine\editor\inspector\components\class.js:147:15
at Array.forEach ()
at Object.update (C:\Cocos\CocosDashboard_1.2.0\resources.editors\Creator\3.5.1\resources\resources\3d\engine\editor\inspector\components\class.js:98:29)
at HTMLElement.update (C:\Cocos\CocosDashboard_1.2.0\resources.editors\Creator\3.5.1\resources\app.asar\node_modules@editor\creator\dist\ui-kit\renderer\components\panel\index.ccc:1:1685)
at C:\Cocos\CocosDashboard_1.2.0\resources.editors\Creator\3.5.1\resources\resources\3d\engine\editor\inspector\contributions\node.js:843:32
at Array.forEach ()

Please advise.


Does the animation module have an import?

No. Added and now works.