class Except extends SetOperation {

    private final Relation left;
    private final Relation right;

    public Except(Relation left, Relation right) {
        this.left = requireNonNull(left, "relation must not be null");
        this.right = requireNonNull(right, "relation must not be null");
    }

    public Relation getLeft() {
        return left;
    }

    public Relation getRight() {
        return right;
    }

    @Override
    public <R, C> R accept(AstVisitor<R, C> visitor, C context) {
        return visitor.visitExcept(this, context);
    }

    @Override
    public boolean equals(Object o) {<FILL_FUNCTION_BODY>}

    @Override
    public int hashCode() {
        return Objects.hash(left, right);
    }

    @Override
    public String toString() {
        return "Except{" +
               "left=" + left +
               ", right=" + right +
               '}';
    }
}

        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        Except except = (Except) o;
        return Objects.equals(left, except.left) &&
               Objects.equals(right, except.right);
    
<methods>public non-sealed void <init>() ,public R accept(AstVisitor<R,C>, C) <variables>