Primer Demo de prueba echo en blender :)

Demo_Addon_Blender.py

# base https://docs.blender.org/api/blender_python_api_2_65_5/info_tutorial_addon.html
bl_info = {
    "name": "pollo con papas",
    "category": "Object",
}

import bpy


class ObjectCursorArray(bpy.types.Operator):
    """Object Cursor Array"""
    bl_idname = "object.cursor_array"
    bl_label = "pollo don papay"
    bl_options = {'REGISTER', 'UNDO'}

    total = bpy.props.IntProperty(name="Steps", default=2, min=1, max=100)

    def execute(self, context):
        scene = bpy.context.scene
        for obj in scene.objects:
            obj.location.x += 1.0

        return {'FINISHED'}


def menu_func(self, context):
    self.layout.operator(ObjectCursorArray.bl_idname)

# store keymaps here to access after registration
addon_keymaps = []


def register():
    bpy.utils.register_class(ObjectCursorArray)
    bpy.types.VIEW3D_MT_object.append(menu_func)

    # handle the keymap
    wm = bpy.context.window_manager
    km = wm.keyconfigs.addon.keymaps.new(name='Object Mode', space_type='EMPTY')
    kmi = km.keymap_items.new(ObjectCursorArray.bl_idname, 'SPACE', 'PRESS', ctrl=True, shift=True)
    kmi.properties.total = 4
    addon_keymaps.append(km)

def unregister():
    bpy.utils.unregister_class(ObjectCursorArray)
    bpy.types.VIEW3D_MT_object.remove(menu_func)

    # handle the keymap
    wm = bpy.context.window_manager
    for km in addon_keymaps:
        wm.keyconfigs.addon.keymaps.remove(km)
    # clear the list
    del addon_keymaps[:]


if __name__ == "__main__":
    register()

Demo_Avanzado.py

import bpy, os

bl_info = {
    "name": "pollo con papas",
    "category": "Object",
}

def ShowMessageBox(message = "", title = "Message Box", icon = 'INFO'):

    def draw(self, context):
        self.layout.label(text=message)
    bpy.context.window_manager.popup_menu(draw, title = title, icon = icon)


class insertVideo(bpy.types.Operator):
    bl_idname = "scene.invideo"
    bl_label = "Insert Video"

    def execute(self, context):
    
        VideoActual = "/home/chepecarlos/2.VideoMusicales/demo/POP.mkv"
       
        # bpy.context.area.type = 'SEQUENCE_EDITOR'
        # FrameActual = bpy.context.scene.frame_current

        if len(bpy.context.selected_sequences) > 0:
            print("Insertando")
        
            Inicio = bpy.context.selected_sequences[0].frame_final_start
            Final = bpy.context.selected_sequences[0].frame_final_end
            Canal = bpy.context.selected_sequences[0].channel + 1

            bpy.ops.sequencer.sound_strip_add(filepath=VideoActual, frame_start=Inicio, channel=Canal)

            bpy.context.selected_sequences[0].show_waveform = True

            bpy.ops.sequencer.split(frame=Final, channel=Canal, type='SOFT', side='RIGHT')

            bpy.ops.sequencer.delete()

            # bpy.context.selected_sequences[0].use_proxy = True
        else:
            print("Selecione una pista")
            ShowMessageBox("Selecione una pista", title="Error")
        return{'FINISHED'}

class MyPanel(bpy.types.Panel):
    """Creates a Panel in the Object properties window"""
    bl_label = "Panel ALSW"
    bl_idname = "my.panel"
    bl_space_type = 'SEQUENCE_EDITOR'
    bl_region_type = 'UI'

    def draw(self, context):
        layout = self.layout

        obj = context.object

        row = layout.row()
        row.label(text="Musica Velocidad")       
        row = layout.row()
        row.operator("scene.invideo", text="Agregar Sonido MrTee")

def register():
    bpy.utils.register_class(MyPanel)
    bpy.utils.register_class(insertVideo)


def unregister():
    bpy.utils.unregister_class(MyPanel)
    bpy.utils.unregister_class(insertVideo)


if __name__ == "__main__":
    register()