In a classroom in Bolivia's second city, El Alto, a group of predominantly indigenous Aymara women are learning self-defense. In a country where government data shows that eight in 10 women experience violence at least once in their lives, the "Warmi Power" project has a keen fanbase. Seeking to "merge psychology with self-defense" - as director Laura Roca puts it - the program has trained 35,000 women across Bolivia since 2015.