This package is available on PyPi:
pip install PLL-Lib
This package is written for the benefit of students taking the 'Phase Locked Loops' Part II experiment as part of the Physics course at Cambridge University.
For a tutorial on its usage, see Phase_Locked_Loops_Automation_Guide.pdf. All the code therein is provided in the Examples directory. For documentation of the functions, see the source, in particular picoscope.py and arduino.py.
Beyond these two files, most of the code is taken from the picosdk-python-wrappers library, taking only those files required for 2000 series Picoscopes. Note that the license for the former allows modification on the condition that license.md be included in any distribution of its code.