A pòh poh dons a jacket in a flowery print that screams springtime. A gùng gung wears a fedora and a butterfly tie. The smiling faces of residents of San Francisco's Chinatown and Chinatowns across the United States and in Canada grace the pages of "Chinatown Pretty: Fashion and Wisdom from Chinatown's Most Stylish Seniors," a book by Portrait Photographer Andria Lo and Writer Valerie Luu.