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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 get_es(url, **kwargs):
 """Create elasticsearch client instance. :param url: elasticsearch url """

    urls = [url] if isinstance(url, str) else url
    kwargs.setdefault('serializer', ElasticJSONSerializer())
    es = elasticsearch.Elasticsearch(urls, **kwargs)
    return es