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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 restructuredtext(text, **kwargs):
 """ Applies reStructuredText conversion to a string, and returns the HTML. """

    from docutils import core
    parts = core.publish_parts(source=text,
                               writer_name='html4css1',
                               **kwargs)
    return parts['fragment']