# in

### Description

`in` can be used to check if there is an entry with a certain key within a dictionary.

### Example 1

```
p is Person
"database" in p.values
```

This returns true if an entry "database" is present in the persons values. If there is no such entry, it will return false.

### Example 2

```
"Last Name" in {"First Name": "Thorben"}
```

This creates a simple dictionary with just one entry with the key "First Name". We then check if the entry "Last Name" exists, which is does not, so this results in a false value.


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