Godot_bridge/addon/menus/__init__.py

from .panel_main import GB_PT_panel_header, GB_PT_panel_parameters, GB_PT_panel_docs

classes = (
    GB_PT_panel_header,
    GB_PT_panel_parameters,
    GB_PT_panel_docs,
)

def register_menus():
    from bpy.utils import register_class
    for cls in classes:
        register_class(cls)

def unregister_menus():
    from bpy.utils import unregister_class
    for cls in classes:
        unregister_class(cls)