Where can I watch Summer Lights in United States?

On the 70th anniversary of the atomic bombing of Hiroshima, Akihiro, a native Japanese filmmaker living in Paris, travels to Japan to interview survivors for a documentary commemorating the victims of the attack. Deeply moved by the interviews, he decides to take a break to wander through the city during which he meets Michiko, a merry, enigmatic young woman. Michiko takes him for a joyful and improvised journey from the city towards the sea where the horrors of the past are mingled with the simplicity of the present.