[IBMiOSS] Python 2 on IBM i 7.3 experience report

I wrote an internal CL command that takes an SQL SELECT statement and
populates an XLSX spreadsheet file.
CMD -> CLP -> PASE -> Python -> Python script

It was quite easy; I had the general notion stubbed out and working with
print statements within minutes. pip install xlsxwriter worked a treat.
Working through the details took most of a day and that includes testing.

The Python script uses ibm_db to access DB2 for i. I used the new DB2
service UDTF qsys2.parse_statement() to extract the column names to be
used as the heading row. For 'select *' statements, this returns zero
columns, but the ibm_db2.columns() function will get the column names
from the table itself.

Error handling is very minimal; it's a tool that probably only I will use.

I was going to say that finding the documentation was kind of a pain,
but it's such a new domain to me that I can't judge until I've got used
to the new idiom.

Mixing CLP, Python, DB2, Excel, and the new DB2 services was very easy.
The only thing I wanted to do but didn't was to feed the exit code back
from Python to the CLP.

Altogether, quite a pleasant experience. I really like the short
feedback loop of an interpreted language.