uniqMap ( ? )

I was wondering how to create or if there is already a function to do a uniqMap ( which should work in a similar manner to sumMap ).
For example given the dataset

```
date | id | value
2021-01-01 | 1 | 1
2021-01-01 | 1 | 2
2021-01-01 | 1 | 2
2021-01-01 | 2 | 1
2021-01-02 | 1 | 1
```

I can do

```sql

SELECT id, sumMap( array(timestamp), array(1)) as sm
FROM table
GROUP BY id

```

to get something like
```
id | sm
1 | [ ['2021-01-01 ', '2021-01-02 '], [3, 1] ]
2 | [ ['2021-01-01 '], [ 1] ]

```

Now, assume that instead of the sum of times a specific `id` is seen daily, what we want is to count the uniq `value` for this id, per day. So the function will look something like

`uniqMap( array(timestamp), value )`

and the result should be:

```
id | sm
1 | [ ['2021-01-01 ', '2021-01-02 '], [2, 1] ]
2 | [ ['2021-01-01 '], [ 1] ]

```