This is a 'translation' of the Getting Started article on Python and Plasma. For the Python Tutorial see here.
The first step for any software project is to set up your project's directory on disk. For this tutorial we are going to create a very simple "hello-web" applet. Create a directory on somewhere called hello-web which in turn contains a contents directory which then contains a code directory. This command below will do all this.
mkdir -p hello-web/contents/code
This creates a simple directory structure which also matches the package structure expected by the plasmapkg command. More on this later.
In the hello-web directory create a file called metadata.desktop and open it in your text editor. Copy the following code into hello-web/metadata.desktop.