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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(self, data, accepted_media_type=None, renderer_context=None):
 """ Renders `data` into serialized YAML. """

        assert yaml, 'YAMLRenderer requires pyyaml to be installed'

        if data is None:
            return ''

        return yaml.dump(
            data,
            stream=None,
            encoding=self.charset,
            Dumper=self.encoder,
            allow_unicode=not self.ensure_ascii,
            default_flow_style=self.default_flow_style
        )