G++ error

In file included from test_student.cpp:3:0:
PrettyPrint.hpp: In instantiation of ‘PrettyPrint::Data<typename std::remove_cv< <template-parameter-1-1> >::type> PrettyPrint::data(const T&) [with T = std::unique_ptr<int, std::default_delete<int> >; typename std::remove_cv< <template-parameter-1-1> >::type = std::unique_ptr<int, std::default_delete<int> >]’:
PrettyPrint.hpp:59:30:   required from ‘std::__cxx11::string PrettyPrint::dataString(const T&) [with T = std::unique_ptr<int, std::default_delete<int> >; std::__cxx11::string = std::__cxx11::basic_string<char>]’
test_student.cpp:48:3:   required from here
PrettyPrint.hpp:39:61: error: use of deleted function ‘std::unique_ptr<_Tp, _Dp>::unique_ptr(const std::unique_ptr<_Tp, _Dp>&) [with _Tp = int; _Dp = std::default_delete<int>]’
 Data<std::remove_cv_t<T>> data(const T& val) { return { val }; }
                                                             ^
In file included from /usr/include/c++/7.2.0/bits/locale_conv.h:41:0,
                 from /usr/include/c++/7.2.0/locale:43,
                 from /usr/include/c++/7.2.0/iomanip:43,
                 from catch.hpp:1430,
                 from test_student.cpp:1:
/usr/include/c++/7.2.0/bits/unique_ptr.h:388:7: note: declared here
       unique_ptr(const unique_ptr&) = delete;
       ^~~~~~~~~~