SQL code not executing from SQL Alchemy in containerized MSSQL -> comment block preventing execution

Background on the problem: I've got MSSQL running in a Docker container, and I'm executing SQL scripts from a file within the container using Python/SQLAlchemy. I know this works because I've been executing other scripts without any problem. But one particular SQL script is executing without any result, and after careful elimination it seems to be caused by a single block of commented out code. Again this doesn't seem to cause an issue elsewhere, and the SQL script also runs faultlessly when executed directly in MSSQL.

The code that calls the SQL script:

with engine.connect() as con:
            with open(file_loc) as file:
                a = file.read()
                a = re.split('\nGO|\nGO\n|\ngo|\ngo\n', a) # split the query at GO
                for q in a:
                    con.execute(sa.text(q))

The code that causes the issue:

-- create new PMT() function
create function [financials].[pmt] (
   @r decimal(38,16)
) returns decimal(24,4)
as
begin
   declare @pmt decimal(24,4);
   ...
   return @pmt;
end;
GO
------ present value <<<<ANY COMMENT HERE PREVENTS THE FUNCTIONS FROM BEING CREATED
create function [financials].[pmt_PV] (
   @pmt decimal(38,16) <<removed trailing comma here
) returns decimal(24,4)
as
begin
   declare @pmt_pv decimal(24,4);
   ...
   return @pmt_pv;
end;
GO

Any comment in the the space marked in the middle prevents the functions from being created.