function new() and _init()

There are two questions I would like to ask:
1. When the gdnative script function parameters have default values, the functions that gdscript calls it must all be assigned values, otherwise the game will exit after running the godot game timeout, and there will be no error message.

2. In gdscript, such as: 'var class=preload("res://**").new()', if the 'new()' function has a value such as 'new(self)', it will prompt an error, The '_init()' parameter is zero.

How should I solve the above two problems.
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