Change the default value of a string column to real uuid()

When I use show create table Posts I see this column:

Slug varchar(400) NOT NULL DEFAULT 'uuid()'

This means that the default value is a string. I want the default string to be a real uuid() function. I want it to become:

Slug varchar(400) NOT NULL DEFAULT uuid()

How can I do that? What query should I write for this? No matter what I do inside the phpMyAdmin or Adminer it does not become what I want. --- I have a column that has 'uuid()' as its default value. I want to change to so that it becomes uuid(). I don't want to create a new column. I don't want to drop the column and recreate it. I want to modify it.