#include <iostream>
#include <future>
#include <chrono>
 
std::string fetchData() {
    std::this_thread::sleep_for(std::chrono::seconds(10)); // Simulates a network call
    return "Data fetched";
}
 
int main() {
    std::cout << "Fetching data..." << std::endl;
    std::future<std::string> futureData = std::async(std::launch::async, fetchData);
    std::string data = futureData.get(); // Blocks until the result is available
    std::cout << data << std::endl; // Output: Data fetched
    return 0;
}
 

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