Help with syntax to avoid -'One or more table references a dynamic Data Source. Not able to save'

Please ignore the above - this is the working version.

Will leave it here in case its of any use to anyone.

Cheers

Thanks PhilipTreacy for the original reply on this post

let
    Source = (EndURL as text) => let
        Source = Json.Document(Web.Contents("https:/urlstartpartishidden/", [RelativePath = "" & EndURL])),
        #"Converted to Table" = Table.FromRecords({Source}),
        #"Expanded dataPoints" = Table.ExpandListColumn(#"Converted to Table", "dataPoints"),
        #"Expanded dataPoints1" = Table.ExpandRecordColumn(#"Expanded dataPoints", "dataPoints", {"x", "y"}, {"dataPoints.x", "dataPoints.y"}),
        #"Changed Type" = Table.TransformColumnTypes(#"Expanded dataPoints1",{{"dataPoints.x", type number}, {"dataPoints.y", type number}, {"dimensionX", type text}, {"dimensionY", type text}, {"isOK", type logical}, {"locationID", Int64.Type}, {"measurementID", Int64.Type}, {"operationID", Int64.Type}, {"timestamp", type datetime}, {"type", type text}, {"unitID", type text}})
    in
        #"Changed Type"
in
    Source