Project the list of geo.model.Point as a separate table:

Class geo.model.Line Extends %Persistent
{
Property points As list Of geo.model.Point(SQLPROJECTION = "table/column");
}

And you can use SQL query (via iris.sql) to get all points in line:

SELECT
    points_latitude, 
    points_longitude
FROM geo_model.Line_points
WHERE Line = ?
ORDER BY element_key

If you have thousands of points that would likely be the fastest way to transfer (barring callin/callout shenanigans).

I guess you need to flush the buffer so only python writes? Something like this should work:

Class Python.App.Dispatch Extends %CSP.REST
{

XData UrlMap [ XMLNamespace = "https://www.intersystems.com/urlmap" ]
{
<Routes>
    <Route Url="/test" Method="GET" Call="Wrapper" />
</Routes>
}

ClassMethod Wrapper()
{
	write *-3
	do ..Hello()
	q $$$OK
}

ClassMethod Hello() [ Language = python ]
{
    import iris

    print('Hello World')
}

}

Calling @Bob Kuszewski

Check $SYSTEM.SQL.Schema.ExportDDL().

do $zf(-100, "/SHELL", "echo", $zcvt("test тест", "O", "UTF8"))
test тест

I usually follow these steps when I have two similar but distinct codebases:

1. Create a new repo.
2. Export everything from the LIVE server into the repo. Commit.
3. Export everything from the TEST server into the repo. Commit.

Commit from step (3) would have all the differences between LIVE and TEST. I assume the code on TEST is newer, so that should be a later commit, but it you want to, you can swap the export order.

Before making a commit (3) you might want to remove trivial differences such as whitespaces, etc. Also Gitlab has a compare mode for commits which automatically ignores whitespace differences.

Is it a password user? Try disabling OS Delegated auth.

While testing, I see I can easily set %session.Data to hold data I want to preserve.  

No problem! I thought you were having issues with that part.

how, on my next API call can I use that session  

You just need to supply the cookies CSPSESSIONID and CSPWSERVERID. With that you'll have the same session. In browsers (and I think in postman) that's automatic, so you don't have to do anything. It should work out of the box as long as you have UseSession set to 1.