23 lines
424 B
Markdown
23 lines
424 B
Markdown
---
|
|
title: find_key
|
|
tags: dictionary,intermediate
|
|
---
|
|
|
|
Returns the first key in the provided dictionary that has the given value.
|
|
|
|
Use `dictionary.items()` and `next()` to return the first key that has a value equal to `val`.
|
|
|
|
```py
|
|
def find_key(dict, val):
|
|
return next(key for key, value in dict.items() if value == val)
|
|
```
|
|
|
|
```py
|
|
ages = {
|
|
"Peter": 10,
|
|
"Isabel": 11,
|
|
"Anna": 9,
|
|
}
|
|
find_key(ages, 11) # "Isabel"
|
|
```
|