def sat(s: str):
 """
 Find a string with certain characters, simple codeforces problem

 Inspired by [Codeforces Problem 133 A](https://codeforces.com/problemset/problem/133/A)
 """
 for c in ["H", "Q", "9"]:
 if c not in s:
 return False
 return True

<details><summary>Reveal solution</summary>
```python
def sol():
 return "world" # replace with your solution
```
</details>