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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def notebook_content(model, notebook_comms_target=None, theme=FromCurdoc):
    ''' Return script and div that will display a Bokeh plot in a Jupyter
    Notebook.

    The data for the plot is stored directly in the returned HTML.

    Args:
        model (Model) : Bokeh object to render

        notebook_comms_target (str, optional) :
            A target name for a Jupyter Comms object that can update
            the document that is rendered to this notebook div

        theme (Theme, optional) :
            Defaults to the ``Theme`` instance in the current document.
            Setting this to ``None`` uses the default theme or the theme
            already specified in the document. Any other value must be an
            instance of the ``Theme`` class.

    Returns:
        script, div, Document

    .. note::
        Assumes :func:`~bokeh.io.notebook.load_notebook` or the equivalent
        has already been executed.

    '''

    if not isinstance(model, Model):
        raise ValueError("notebook_content expects a single Model instance")

    # Comms handling relies on the fact that the new_doc returned here
    # has models with the same IDs as they were started with
    with OutputDocumentFor([model], apply_theme=theme, always_new=True) as new_doc:
        (docs_json, [render_item]) = standalone_docs_json_and_render_items([model])

    div = div_for_render_item(render_item)

    render_item = render_item.to_json()
    if notebook_comms_target:
        render_item["notebook_comms_target"] = notebook_comms_target

    script = DOC_NB_JS.render(
        docs_json=serialize_json(docs_json),
        render_items=serialize_json([render_item]),
    )

    return encode_utf8(script), encode_utf8(div), new_doc