How to link a text object body to the edge length of another object with Python?

Question

I would like to create a tool to measure object length dynamically.

Something like a group of 2 objects:

• 1 unique edge object
• 1 text object (children of the previous)

How to link edge length to the text object body?

Answer 1

Dolf Veenvliet already dit it several years ago! Thank you to Duarte who provided the link.

The Caliper Blender Addon

The script