How to use the portray.exceptions.DocumentationAlreadyExists function in portray

def test_as_html(temporary_dir, project_dir, chdir):
    with chdir(temporary_dir):
        # Directory with no project
        with pytest.raises(exceptions.NoProjectFound):
            api.as_html()

        # Rendering should succeed as soon as a project is within the directory
        temp_project_dir = os.path.join(temporary_dir, "portray")
        shutil.copytree(project_dir, temp_project_dir)
        with chdir(temp_project_dir):
            api.as_html()

            # Rendering a second time should fail
            with pytest.raises(exceptions.DocumentationAlreadyExists):
                api.as_html()

            # Unless we enable overwritting destination
            api.as_html(overwrite=True)

            # Or, we output to a different location
            with tempfile.TemporaryDirectory() as new_temp_directory:
                api.as_html(output_dir=os.path.join(new_temp_directory, "site"))

Behind the scenes:

    - A temporary directory is created and your code is copy and pasted there
    - pdoc is ran over your code with the output sent into the temporary directory
        as Markdown documents
    - MkDocs is ran over all of your projects Markdown documents including those
        generated py pdoc. MkDocs outputs an HTML representation to a new temporary
        directory.
    - The html temporary directory is copied into your specified output location
    - Both temporary directories are deleted.
    """
    if os.path.exists(config["output_dir"]):
        if overwrite:
            shutil.rmtree(config["output_dir"])
        else:
            raise DocumentationAlreadyExists(config["output_dir"])

    with documentation_in_temp_folder(config) as documentation_output:  # type: str
        shutil.copytree(documentation_output, config["output_dir"])