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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 get_rendered_toctree(builder, docname, prune=False, collapse=True):
 """Build the toctree relative to the named document, with the given parameters, and then return the rendered HTML fragment. """

    fulltoc = build_full_toctree(builder,
                                 docname,
                                 prune=prune,
                                 collapse=collapse,
                                 )
    rendered_toc = builder.render_partial(fulltoc)['fragment']
    return rendered_toc