確認有安裝 ipykernel 後，terminal 下移動到新建的虛擬環境資料夾下，例如 my_env_name 執行下列指令:
python -m ipykernel install --user --name=<my_env_name>
ref: Create Virtual Environment using “virtualenv” and add it to Jupyter Notebook | by B. Chen | Towards Data Science