These symbols have been generated by Ezra as detailed here: https://core-electronics.com.au/projects/piicodev-schematic-system/
In this repository you will find symbols in the following formats:
- PNG
- SVG
- DrawIO Library
When you open DrawIO there is an option under File to Open Library From with a number of options for library sources.
The file to open is "PiicoDevSymbols.xml". This can be downloaded or saved where you wish. Alternatively, you can Open a library from a URL and then copy/paste the URL below:
https://raw.githubusercontent.com/garynthompson/piicodev-symbols/main/DrawIO/PiicoDevSymbols.xml