How to use the libusb1.libusb_init function in libusb1

def open(self):
        """
        Finish context initialisation, as is normally done in __enter__ .

        This happens automatically on the first method call needing access to
        the uninitialised properties, but with a warning.
        Call this method ONLY if your usage pattern prevents you from using the
            with USBContext() as contewt:
        form: this means there are ways to avoid calling close(), which can
        cause issues particularly hard to debug (ex: interpreter hangs on
        exit).
        """
        assert self.__context_refcount == 0
        mayRaiseUSBError(libusb1.libusb_init(byref(self.__context_p)))
        return self

def __init__(self):
        """
        Create a new USB context.
        """
        context_p = libusb1.libusb_context_p()
        result = libusb1.libusb_init(byref(context_p))
        if result:
            raise libusb1.USBError(result)
        self.__context_p = context_p

def __init__(self):
        """
        Create a new USB context.
        """
        # Used to prevent an exit to cause a segfault if a concurrent thread
        # is still in libusb.
        self.__context_refcount = 0
        self.__context_cond = threading.Condition()
        context_p = libusb1.libusb_context_p()
        result = libusb1.libusb_init(byref(context_p))
        if result:
            raise libusb1.USBError(result)
        self.__context_p = context_p