template<class charT, class traits, class Duration>
basic_ostream<charT, traits>&
operator<<(basic_ostream<charT, traits>& os, const local_time<Duration>& lt);
template<class charT, class traits, class Duration, class Alloc = allocator<charT>>
basic_istream<charT, traits>&
from_stream(basic_istream<charT, traits>& is, const charT* fmt,
local_time<Duration>& tp, basic_string<charT, traits, Alloc>* abbrev = nullptr,
minutes* offset = nullptr);