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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 render_html(input_text, **context):
 """ A module-level convenience method that creates a default bbcode parser, and renders the input string as HTML. """

    global g_parser
    if g_parser is None:
        g_parser = Parser()
    return g_parser.format(input_text, **context)