# ZDIFFSTORE

> Writes the difference between sets to a new key.

## Arguments 

<ParamField body="destination" type="str" required>
  The key to write the difference to.
</ParamField>

<ParamField body="keys" type="List[str]" required>
  The keys to compare.
</ParamField>

## Response

<ResponseField type="int">
    The number of elements in the resulting set.
</ResponseField>

<RequestExample>
```py Example
redis.zadd("key1", {"a": 1, "b": 2, "c": 3})

redis.zadd("key2", {"c": 3, "d": 4, "e": 5})

# a and b
assert redis.zdiffstore("dest", ["key1", "key2"]) == 2
```
</RequestExample>