Iterating through a workflow property with type Dictionary

[weirdyang]

I have a Property on my workflow which is a dictionary, when I use the liquid json filter on it, I get

{"Count":1,"Keys":["file-name"]}

I tried to iterate thru the keys property with the following code, but nothing is rendered

{% for item in Workflow.Properties["output"].Keys %}
   {{ item | raw }}
 {% endfor %}

I have also tried Workflow.Properties["output"]["Keys"] but it's null

How do I render the keys of the JObject/Dictionary or iterate through them?