How to save image metadata in PNG files using Python? or Best way to save image metadata to PNG with

For *lightweight* python save image metadata png, skip the big libs.

`png` module (yes, that’s its name) is tiny and lets you inject raw chunks.

Example:
```python
import png
writer = png.Writer(...)
writer.chunks.append(("tEXt", "Author\x00Me"))
```

Weird syntax, but it *works*.