/******************************************************************************
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#include <iostream>
#include <set>
namespace hl = std;
template <template <typename... > class Tmp> struct holder {};
template <typename T> struct extract : hl::false_type {};
template <typename... Ts, template <typename... > class Tmpl>
struct extract<Tmpl<Ts...>> : hl::true_type
{
typedef holder<Tmpl> type;
};
int main()
{
typedef std::set<int> T;
std::cout<<"Hello World " << std::is_same<typename extract<T>::type, holder<std::set>>::value << std::endl;
return 0;
}