Some older apartments in Paris were designed to have a shared bathroom on each floor, not in each apartment. When modernized, the apartments needed to have their own bathrooms but the plumbing in the building wasn't designed for it, so a special kind of "electric" toilet was installed in those units. Our first apartment in Paris had one of these, and although the end result is the same as a regular toilet, you have to use a special kind of toilet paper that comes in individual sheets (around the size of 2 regular toilet paper squares), and you have to be careful not to throw anything into the toilet.