Dots Per Inch (aka Pixels Per Inch)
Deprecated: This function used to set a global default DPI. However, it only worked if it was called before any rsvg.Handle objects had been created; it would not work after that. To avoid global mutable state, please use Handle.setDpi instead.
2.8
Do not use this function. Create an rsvg.Handle and call Handle.setDpi on it instead.