As you wrote,  %XML.TextReader is used to read arbtrary XML documents. "A text where in the middle a little bit xml-structure sits" isn't XML!

Maybe there is a Pyhton library for extracting XML from a text. If not, probably you have to read char-after-char, count each "<" (+1) and ">" (-1) and if the counter is 0 then between the first "<"  and the last ">" probably you have a correct XML structure. Oh, and don't forget for <![CDATA[...]]> sequences, which makes the reading more challenging.

Your subject (compilation error iris terminal class not found) and the screenshot
- workinhg on Class: Class TESTsAMTraining.NewClassDemo1
- calling a class: do ##class(MyCos.COSTest).Main
- and the error message: <CLASS DOES NOT EXISTS>

do not match!

I do not see anything about a "compilation error" on the other hand, there is an error saying, a class do not exists.

So please help us to help you and try to give us correct data about your problem.
Thank you.

Just came to my mind
- Cache-5.0.x is likely to be 32 Bit version, Win-11 is 64 Bit (only) (in case, the application uses some .dll, .ocx, etc.)
- unlikely that you use it, but as a hint, LAT is not supported anymore
- user database is now provided by ISC. In case your application maintains its own users, you can still use your own user database, but the login process will require some "adaption"

As a first step, I would contact your ISC Sales because Cache-5.0.x licenses neither work with (the latest) Cache nor with IRIS. Second, there was a lot of change between Cache-5.0.x and recent Cache/IRIS versions, so I would check to see if there are any problems to expect. A customer of mine "upgraded" fom Cache-5.0.21 to IRIS  some four years ago...

Just for the case, you are lost in the working memory space and desperately searching the spot(s) in your programm where a specific object is once again referenced, here a small handy method which could help you

/// find all variables which contain a given object(reference)
/// 
/// I: the OREF you looking for
/// 
/// O: "" if the spool-device can't be opened
///    [] if no variables contain the given OREF
///    [var1, var2, ... varN] an array of variable names (incl. subscripted and orefs)
///    
ClassMethod FindObject(obj)
{
	set res=[]
	if $d(%)#10,%=obj do res.%Push("%")
	new % set %=obj kill obj
	
	lock +^SPOOL("nextID")			// adapt this lines
	open 2:($o(^SPOOL(""),-1)+1):1	// to your method of
	lock -^SPOOL("nextID")			// creating new spool IDs
	
	if $t {
		use 2
		set spl=$zb
		do $system.OBJ.ShowReferences(.%,1)
		
		for i=1:1:$za-1 {
			set x=$p($zstrip(^SPOOL(spl,i),"<=>w",$c(13,10))," ",3)
			do:x]"%.~" res.%Push(x)
		}
		close 2
		kill ^SPOOL(spl)
		
	} else { set res="" }
	
	quit res
}

Example

USER>kill
USER>set pers=##class(DC.Person).%OpenId(1)
USER>set temp=pers, zz(3)=temp
USER>write ##class(DC.Help).FindObject(pers).%ToJSON()
["pers","temp","zz(3)"]

I'm not sure wha you want to achive, so I ask a puzzling question: do you want to create dungling object? "I want to remove the object from memory even if it is still referenced in memory", as I understand, would free the memory used by an object but let the object referenc(es) intact, so the reference now would point into nirvana. Is that what you want to do? Why? Can you a little bit elaborate, what is your target or the background respectively?

I have a limited embedded python experience but if you can manage to get a (COS)%List from python then the solution is:

set $lb(val1, val2, val2, ...) = ConvertPythonTupelToCOSList(pythonfunction(param))
set $lb(val1, val2, val2, ...) = ConvertPythonListToCOSList(pythonfunction(param))

/// For example
ClassMethod Test()
{
  return $lb(11,22,33)
}

set $lb(a,b,c)=##class(Some.Class).Test()
write a,?5,b,?10,c ---> 11   22   33

I have no background information about your problem, but somehow I have the feeling, your have an organizational problem and not an isolational.

If one or more processes perform certain work under transaction and at the same time they feed a queue too ( I call it the WorkQueue) BEFORE the transaction is finished AND the queue is processed in parallel by an third process, then:
- either the third process (that with $order()) has to wait for the transaction to be finished or
- the process under transaction has to inform that third process about the outcome (i.e. rollback) of the transaction by feeding an second queue (I call this as the RolbackQueue).

The above implies, that
- before I put an item into the RollbackQueue, I would check, if it's already processed (from the WorkQueue), and if not, remove it from the WorkQueue and do not put it into the RollbackQueue
- in that third process, before processing an item, I would check, if that item is in the RollbackQueue. If yes, just do not process it (and remove from both queues)

As simple as that, merely I don't know your requirements.

It's not a "slight difference", it's a real difference, because you are using two different commands (a DO and an IF command)

set a = -1        // sets the variable a to -1
do $increment(a,1) zw "test" // increments <a> by 1, <a> is now 0
                             // the $increment() returns (the value of <a>)
                             // but the DO command do not expects a return value
                             // so the returned 0 is disposed
                             // hereinafter the next command on the line (zw) is executed
if $increment(a,1) zw "test" // increments <a> by 1, <a> is now 0
                             // the $increment() returns (the value of <a>) which is 0
                             // the IF command takes the returned value (0) but the value is
                             // "FALSE", hence the rest of the line is skipped (old style IF)
                             

If yo want to use the IF command and want both commands to be executed and have them on one line then:

// you have several options, a few of them
//
if $increment(a,1) { } zw "test" // empty IF-statement
if $increment(a,1)!1 zw "test"   // an IF with a forced outcome
if $increment(a,1)=a zw "test"   // if a=$increment(a,1) WON'T WORK !!!
//
// The only limit is only your imagination...

By the way, it's not a good idea using commands/functions with abbrevations and at the same time using mixed cases. In your examples I had to take a second look to realize, the one is a capital "i" and not a lowercase "L"

if $I(a,1) // increment a by 1
if $l(a,1) // return the subfieldcount from <a>, delimited by the character "1"

This works for me (pay attention to the semicolons!)

ClassMethod numpytest() As %String [ Language = python ]
{
 import numpy as np
 import math
 arr = np.array([1, 2, 3, 4, 5]); print(arr); x=np.random.randint(1, 15, 1) # generate a number between 1 and 15
 print("Random num=",x)
 y=math.pi
 print("This is pi:",y)
 x="hello world"
 print(x)
 a=2+5
 print("a=",a)
}

an the output is


USER>d ##class(Py.Demo).numpytest()
[1 2 3 4 5]
Random num= [13]
This is pi: 3.141592653589793
hello world
a= 7

USER>w $zv
IRIS for UNIX (Ubuntu Server LTS for x86-64) 2021.2 (Build 649U) Thu Jan 20 2022 08:49:51 EST
USER>