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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 add_simple_formatter(self, tag_name, format_string, **kwargs):
 """ Installs a formatter that takes the tag options dictionary, puts a value key in it, and uses it as a format dictionary to the given format string. """

        def _render(name, value, options, parent, context):
            fmt = {}
            if options:
                fmt.update(options)
            fmt.update({'value': value})
            return format_string % fmt
        self.add_formatter(tag_name, _render, **kwargs)