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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 codemirror_html(self, config_name, varname, element_id):
 """ Render HTML for a CodeMirror instance. Since a CodeMirror instance have to be attached to a HTML element, this method requires a HTML element identifier with or without the ``#`` prefix, it depends from template in ``settings.CODEMIRROR_FIELD_INIT_JS`` (default one require to not prefix with ``#``). Arguments: config_name (string):
 A registred config name. varname (string):
 A Javascript variable name. element_id (string):
 An HTML element identifier (without leading ``#``) to attach to a CodeMirror instance. Returns: string: HTML to instanciate CodeMirror for a field input. """

        parameters = json.dumps(self.get_codemirror_parameters(config_name),
                                sort_keys=True)
        return settings.CODEMIRROR_FIELD_INIT_JS.format(
            varname=varname,
            inputid=element_id,
            settings=parameters,
        )