Charlieplex displays use a unique wiring structure so many LEDs can be controlled with just a few shared wires. There are even specialized driver chips like the IS31FL3731 which can control a large number of Charlieplexed LEDs using pulse-width modulation to dim and brighten them at different intensity levels. Adafruit's Charlieplex FeatherWing and breakout use this driver chip to make a large matrix of tiny LEDs that are super easy to control. Using a CircuitPython or MicroPython IS31FL3731 module you can even control Charlieplex matrices from Python code! This guide explores how to use the Charlieplex FeatherWing and breakout with CircuitPython.
This guide is no longer supported. Please checkout IS31FL3731 guide for CircuitPython and Python usage of CharliePlex matrices: https://learn.adafruit.com/i31fl3731-16x9-charliplexed-pwm-led-driver/python-circuitpython
Note the video above was made showing the MicroPython version of this library. Follow the guide to see both CircuitPython and MicroPython versions of the IS31FL3731 library.