Return the existing instance of #PeasEngine or a subclass of it.
If no #PeasEngine subclass has been instantiated yet, the first call
of this function will return a new instance of #PeasEngine.
Note: this function should never be used when multiple threads are
using libpeas API as it is not thread-safe.
Return the existing instance of #PeasEngine or a subclass of it. If no #PeasEngine subclass has been instantiated yet, the first call of this function will return a new instance of #PeasEngine.
Note: this function should never be used when multiple threads are using libpeas API as it is not thread-safe.
Return: the existing instance of #PeasEngine.