index.html

import requests

def fetch_url(url, method='GET', data=None, headers=None):
    """
    Fetches data from a given URL using GET or POST method.
    :param url: URL to fetch data from.
    :param method: HTTP method ('GET' or 'POST').
    :param data: Data for POST request.
    :param headers: Additional headers if required.
    :return: Response text or error message.
    """
    try:
        if method.upper() == 'POST':
            response = requests.post(url, data=data, headers=headers)
        else:
            response = requests.get(url, headers=headers)
        
        response.raise_for_status()  # Raise HTTPError for bad responses (4xx and 5xx)
        return response.text
    except requests.exceptions.RequestException as e:
        return f"Error: {e}"

# Example Usage
if _name_ == "_main_":
    test_url = "https://jsonplaceholder.typicode.com/posts/1"
    print(fetch_url(test_url))