pyqt is created by SIP, and SIP support signal and slot.
qt use moc to create a moc data about the signal and slot functions.
and qt search slot by index the function name.
and I want to know how pyqt archive this?
this is a critical question for better understanding pyqt...
From memory, I believe that PyQt initially used only proxy objects to handle signals and slots, making it possible for any Python callable to be used as a slot and pretty much any signal to be emitted. At some point, support for static meta-objects was added, making it possible for Python to be used to write Qt Designer plugins.
I think that some Qt-specific handling code was moved from SIP into PyQt at some point, and some refactoring has taken place over time, so I think it's worth looking at PyQt's internals to start with.