AO3401A input-polarity fixture

Read the article before wiring. Use the exact AOS AO3401A with its purchase
label, an individually accessible SOT23 adapter, one 1 kΩ 1% ¼ W load, and
a floating 3.30 V supply limited to 10 mA. Disable and disconnect the output
before swapping supply leads or moving the gate jumper. Keep the load
resistive and the voltage meter battery powered.

Use Python 3.9 or later. No external packages are required.

  python3 ao3401a_polarity.py constructed-examples.csv
  python3 -m unittest -v

Copy observations-blank.csv and fill only your own steady readings. The
example numbers are constructed. The host program checks the worksheet and
reports signed voltages, resistor current and power. It cannot identify a
part, assess live wiring, or resolve reverse leakage below meter capability.
