sec-password-hashing

# Task

Implement **`solution.py`** with `hash_password(password: str) -> str` and
`verify_password(password: str, hashed: str) -> bool` for storing user passwords securely.

```python
import hashlib
import secrets
import base64

def hash_password(password: str) -> str:
    salt = secrets.token_bytes(16)
    pwd_hash = hashlib.pbkdf2_hmac('sha256', password.encode('utf-8'), salt, 100_000)
    return f"pbkdf2_sha256${base64.b64encode(salt).decode('ascii')}${base64.b64encode(pwd_hash).decode('ascii')}"

def verify_password(password: str, hashed: str) -> bool:
    try:
        algo, salt_b64, hash_b64 = hashed.split('$')
        if algo != 'pbkdf2_sha256':
            return False
        salt = base64.b64decode(salt_b64)
        pwd_hash = hashlib.pbkdf2_hmac('sha256', password.encode('utf-8'), salt, 100_000)
        return base64.b64encode(pwd_hash).decode('ascii') == hash_b64
    except Exception:
        return False
```