I want to generate a random uuid but I got following error:

ERROR:  42601: syntax error at or near "uuid_generate_v4"
LINE 2:   id UUID uuid_generate_v4() PRIMARY KEY,

Here is my sql code:

CREATE table cars (
  id UUID uuid_generate_v4() PRIMARY KEY,
  name varchar,
  cover varchar,
  price varchar,
  engine varchar,
  fuel varchar,
  firstRegistration varchar,
  ps smallint,
  km int,
  color varchar,
  environment text,
  equipment text,
  description text,
  created_at timestamp not null default current_timestamp
);