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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 to_json(self, path=None, html_out=False, html_path='vega_template.html', validate=False, pretty_print=True):
 """Convert object to JSON Parameters path: string, default None Path to write JSON out. If there is no path provided, JSON will be returned as a string to the console. html_out: boolean, default False If True, vincent will output an simple HTML scaffold to visualize the vega json output. html_path: string, default 'vega_template.html' Path for the html file (if html_out=True) validate : boolean If True, call the object's `validate` method before serializing. Default is False. pretty_print : boolean If True (default), JSON is printed in more-readable form with indentation and spaces. Returns ------- string JSON serialization of the class's grammar properties. """

        if validate:
            self.validate()

        if pretty_print:
            dumps_args = {'indent': 2, 'separators': (',', ': ')}
        else:
            dumps_args = {}

        def encoder(obj):
            if hasattr(obj, 'grammar'):
                return obj.grammar

        if html_out:
            template = Template(
                str(resource_string('vincent', 'vega_template.html')))
            with open(html_path, 'w') as f:
                f.write(template.substitute(path=path))

        if path:
            with open(path, 'w') as f:
                json.dump(self.grammar, f, default=encoder, sort_keys=True,
                          **dumps_args)
        else:
            return json.dumps(self.grammar, default=encoder, sort_keys=True,
                              **dumps_args)