1. 创建一个自定义加法操作符（Operator）。

import bpy

class CustomOperator(bpy.types.Operator):
    bl_idname = "strip.custom_operator"
    bl_label = "Custom Strip"

    def execute(self, context):
        return {'FINISHED'}

2. 创建一个自定义属性。

import bpy

class CustomStripProperties(bpy.types.PropertyGroup):
    custom_property: bpy.props.StringProperty(name="Custom Property")

3. 创建一个面板并在其中显示自定义属性。

import bpy

class CustomPanel(bpy.types.Panel):
    bl_idname = "panel.custom_panel"
    bl_label = "Custom Panel"
    bl_space_type = "SEQUENCE_EDITOR"
    bl_region_type = "UI"
    bl_category = "Custom Category"

    def draw(self, context):
        layout = self.layout
        strip = context.selected_sequences[0]

        layout.prop(strip, "custom_property")

4. 注册上述三个自定义类。

import bpy

class CustomOperator(bpy.types.Operator):
    bl_idname = "strip.custom_operator"
    bl_label = "Custom Strip"

    def execute(self, context):
        return {'FINISHED'}

class CustomStripProperties(bpy.types.PropertyGroup):
    custom_property: bpy.props.StringProperty(name="Custom Property")

class CustomPanel(bpy.types.Panel):
    bl_idname = "panel.custom_panel"
    bl_label = "Custom Panel"
    bl_space_type = "SEQUENCE_EDITOR"
    bl_region_type = "UI"
    bl_category = "Custom Category"

    def draw(self, context):
        layout = self.layout
        strip = context.selected_sequences[0]

        layout.prop(strip, "custom_property")

def register():
    bpy.utils.register_class(CustomOperator)
    bpy.utils.register_class(CustomStripProperties)
    bpy.utils.register_class(CustomPanel)

    bpy.types.Sequence.custom_props = bpy.props.PointerProperty(type=CustomStripProperties)

def unregister():
    bpy.utils.unregister_class(CustomOperator)
    bpy.utils.unregister_class(CustomStripProperties)
    bpy.utils.unregister_class(CustomPanel)

    del bpy.types.Sequence.custom_props

5. 定义一个函数，用于在添加自定义视频条时执行自定义代码。

import bpy

def custom_video_strip(code):
    bpy.ops.sequencer.movie_strip_add()
    strip = bpy.context.selected_sequences[0]

    strip.custom_props.custom_property = code

6. 在需要添加自定义视频条的地方，调用custom_video_strip函数，并传递自定义代码。

import bpy

def main():
    custom_video_strip("print('Hello, custom strip!')")

if __name__ == "__main__":
    main()

7. 运行脚本，并在序列编辑器中添加一个自定义视频条，可以看到在自定义面板中显示了自定义属性。

以上是通过代码、属性和面板UI制作自定义视频条的具体和代码示例。