he-010

# HumanEval/10

Implement a file **`solution.py`** that completes the function below. Keep the given name and signature; your file must define it at module level.

```python


def is_palindrome(string: str) -> bool:
    """ Test if given string is a palindrome """
    return string == string[::-1]


def make_palindrome(string: str) -> str:
    """ Find the shortest palindrome that begins with a supplied string.
    Algorithm idea is simple:
    - Find the longest postfix of supplied string that is a palindrome.
    - Append to the end of the string reverse of a string prefix that comes before the palindromic suffix.
    >>> make_palindrome('')
    ''
    >>> make_palindrome('cat')
    'catac'
    >>> make_palindrome('cata')
    'catac'
    """
```

<!-- imported from OpenAI HumanEval (HumanEval/10) -->

# Auto-generated from OpenAI HumanEval HumanEval/10. Do not edit by hand.
from solution import *  # noqa: F401,F403 (prompt helpers may be referenced by tests)
from solution import make_palindrome as candidate

METADATA = {
    'author': 'jt',
    'dataset': 'test'
}


def check(candidate):
    assert candidate('') == ''
    assert candidate('x') == 'x'
    assert candidate('xyz') == 'xyzyx'
    assert candidate('xyx') == 'xyx'
    assert candidate('jerry') == 'jerryrrej'


def test_he_010():
    check(candidate)

You are an expert programmer. Solve the task exactly as specified. Output your solution as fenced code blocks using the required file name(s) and the exact function/type signatures requested. Prefer correctness; do not include prose outside code unless asked.

```python
def is_palindrome(string: str) -> bool:
    """ Test if given string is a palindrome """
    return string == string[::-1]


def make_palindrome(string: str) -> str:
    """ Find the shortest palindrome that begins with a supplied string.
    Algorithm idea is simple:
    - Find the longest postfix of supplied string that is a palindrome.
    - Append to the end of the string reverse of a string prefix that comes before the palindromic suffix.
    >>> make_palindrome('')
    ''
    >>> make_palindrome('cat')
    'catac'
    >>> make_palindrome('cata')
    'catac'
    """
    if not string:
        return ""
    
    # Find the longest palindromic postfix
    for i in range(len(string)):
        if is_palindrome(string[i:]):
            # Append the reverse of the prefix to make it a palindrome
            return string + string[:i][::-1]
    
    # If no palindromic postfix found (shouldn't happen), append reverse of entire string except last char
    return string + string[:-1][::-1]
```