1. bpyによるadd-onのインストールと有効化
   
2. bpyによるadd-on使用例
   

def install_and_enable_addon(
        addon_directory                         # 格納ディレクトリ
    ,   url                                     # ダウンロードURL
    ,   addon_name                              # アドオン名
    ,   addon_name_head="bl_ext.blender_org."   # アドオン名接頭辞
    ):
    # 保存先ZIPファイルのパス
    local_zip_path = os.path.join(addon_directory, 'addon.zip')
    # アドオンのインストール先パス
    addon_path = os.path.join(addon_directory, addon_name)
    # アドオンがすでにインストールされている場合
    if os.path.exists(addon_path):
        print(f"Addon '{addon_name}' already exists. Skipping download and installation.")
        # アドオン有効化
        addon_name = addon_name_head + addon_name
        if addon_name in bpy.context.preferences.addons:
            print(f"Addon '{addon_name}' is already enabled.")
        else:
            try:
                # アドオン有効化
                bpy.ops.preferences.addon_enable(module=addon_name)
                print(f"Addon '{addon_name}' enabled successfully.")
            except RuntimeError as e:
                print(f"Failed to enable addon '{addon_name}': {e}")
        return
    else:
        # URLからZIPファイルダウンロード
        try:
            response = requests.get(url, stream=True)
            response.raise_for_status()  # HTTPエラーチェック
            with open(local_zip_path, 'wb') as file:
                for chunk in response.iter_content(chunk_size=8192):
                    file.write(chunk)
            print("Download completed.")
        except requests.exceptions.RequestException as e:
            print(f"Failed to download file: {e}")
            return
        # ZIPファイル解凍
        try:
            with zipfile.ZipFile(local_zip_path, 'r') as zip_ref:
                zip_ref.extractall(addon_directory+"/"+addon_name)
            print("Extraction completed.")
        except zipfile.BadZipFile as e:
            print(f"Failed to extract ZIP file: {e}")
            return
        # ZIPファイルを削除
        os.remove(local_zip_path)
        # アドオン有効化
        addon_name = addon_name_head + addon_name
        if addon_name not in bpy.context.preferences.addons:
            try:
                bpy.ops.preferences.addon_enable(module=addon_name)
                print(f"Addon '{addon_name}' enabled successfully.")
            except RuntimeError as e:
                print(f"Failed to enable addon '{addon_name}': {e}")
        else:
            print(f"Addon '{addon_name}' is already enabled.")

# Extensions Download Directry
addon_directory = "C:/Users/Username/AppData/Roaming/Blender Foundation/Blender/4.2/extensions/blender_org"

def Base_create():
    bpy.ops.object.mode_set(mode='OBJECT')

    # Extensions(アドオン)追加
    addon_url = "https://extensions.blender.org/download/sha256:49a1c484cd1cf535901f65f1425f06812bbef6c329a6cb1eb741b35c8ea17c06/add-on-sapling-tree-gen-v0.3.6.zip"
    addon_name = "sapling_tree_gen"
    install_and_enable_addon(
        addon_directory # 格納ディレクトリ
    ,   addon_url       # ダウンロードURL
    ,   addon_name      # アドオン名(ディレクトリ名)
    )

    # Tree 追加
    bpy.ops.curve.tree_add(
        do_update=True
    ,   bevel=True
    ,   prune=False
    ,   showLeaves=True
    ,   useArm=False
    ,   seed=0
    ,   handleType='0'
    ,   levels=1
    ,   length=(0.7, 0.6, 0.5, 0.1)
    ,   lengthV=(0, 0.1, 0, 0)
    ,   taperCrown=0.5
    ,   branches=(0, 55, 10, 1)
    ,   curveRes=(8, 5, 3, 1)
    ,   curve=(0, -15, 0, 0)
    ,   curveV=(20, 50, 75, 0)
    ,   curveBack=(0, 0, 0, 0)
    ,   baseSplits=2
    ,   segSplits=(0.1, 0.5, 0.2, 0)
    ,   splitByLen=True
    ,   rMode='rotate'
    ,   splitAngle=(30, 30, 22, 0)
    ,   splitAngleV=(5, 5, 5, 0)
    ,   scale=0.1
    ,   scaleV=1.1
    ,   attractUp=(3.5, -1.89984, 0, 0)
    ,   attractOut=(0, 0.8, 0, 0)
    ,   shape='7'
    ,   shapeS='10'
    ,   customShape=(0.5, 1, 0.3, 0.5)
    ,   branchDist=1.5
    ,   nrings=0
    ,   baseSize=0.3
    ,   baseSize_s=0.16
    ,   splitHeight=0.2
    ,   splitBias=0.55
    ,   ratio=0.015
    ,   minRadius=0.0015
    ,   closeTip=False
    ,   rootFlare=1
    ,   autoTaper=True
    ,   taper=(1, 1, 1, 1)
    ,   radiusTweak=(1, 1, 1, 1)
    ,   ratioPower=1.2
    ,   downAngle=(0, 26.21, 52.56, 30)
    ,   downAngleV=(0, 10, 10, 10)
    ,   useOldDownAngle=True
    ,   useParentAngle=True
    ,   rotate=(99.5, 137.5, 137.5, 137.5)
    ,   rotateV=(15, 0, 0, 0)
    ,   scale0=1
    ,   scaleV0=0.1
    ,   pruneWidth=0.34
    ,   pruneBase=0.12
    ,   pruneWidthPeak=0.5
    ,   prunePowerHigh=0.5
    ,   prunePowerLow=0.001
    ,   pruneRatio=0.75
    ,   leaves=15
    ,   leafDownAngle=45
    ,   leafDownAngleV=-10
    ,   leafRotate=137.5
    ,   leafRotateV=15
    ,   leafScale=0.1
    ,   leafScaleX=0.2
    ,   leafScaleT=0.1
    ,   leafScaleV=0.15
    ,   leafShape='hex'
    ,   bend=0
    ,   leafangle=-45
    ,   horzLeaves=True
    ,   leafDist='6'
    ,   bevelRes=1
    ,   resU=4
    ,   armAnim=False
    ,   previewArm=False
    ,   leafAnim=False
    ,   frameRate=1
    ,   loopFrames=0
    ,   wind=1
    ,   gust=1
    ,   gustF=0.075
    ,   af1=1
    ,   af2=1
    ,   af3=4
    ,   makeMesh=False
    ,   armLevels=2
    ,   boneStep=(1, 1, 1, 1)
    )

Base_create()