import requests

def summarize_text(api_key, text):
    headers = {
        "Authorization": f"Bearer {api_key}",
        "Content-Type": "application/json"
    }
    data = {
        "text": text,
        "length": "short"
    }
    response = requests.post("https://api.ai-summarize.com/v1/summarize", headers=headers, json=data)
    response.raise_for_status()
    return response.json()["summary"]

# Sử dụng ví dụ
api_key = "YOUR_AI_API_KEY"
long_article = "..."  # Nội dung bài báo dài
summary = summarize_text(api_key, long_article)
print(summary)

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract PremiumAPIAccess {
    address public apiProvider;
    mapping(address => bool) public hasAccess;
    mapping(address => uint256) public accessExpiry;

    event AccessGranted(address indexed user, uint256 expiryTime);
    event AccessRevoked(address indexed user);

    constructor() {
        apiProvider = msg.sender;
    }

    modifier onlyApiProvider() {
        require(msg.sender == apiProvider, "Only API provider can call this function");
        _;
    }

    function grantAccess(address _user, uint256 _durationInDays) public onlyApiProvider {
        accessExpiry[_user] = block.timestamp + (_durationInDays * 1 days);
        hasAccess[_user] = true;
        emit AccessGranted(_user, accessExpiry[_user]);
    }

    function revokeAccess(address _user) public onlyApiProvider {
        hasAccess[_user] = false;
        accessExpiry[_user] = 0;
        emit AccessRevoked(_user);
    }

    function checkAccess(address _user) public view returns (bool) {
        return hasAccess[_user] && (accessExpiry[_user] > block.timestamp);
    }
}