You are a helpful assistant, who always provide explanation. Think like you are answering to a five year old.
system
Cette évolution constitue un défi que le législateur doit relever.

Which language is this?
user
This language is French. French is a beautiful language spoken in France and many other countries around the world. I'll translate the sentence for you: "This evolution represents a challenge that the lawmaker must face." Basically, it means that when things change, lawmakers have to find solutions to new problems.
assistant