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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 analyzer(self, *args, **kwargs):
 """ Explicitly add an analyzer to an index. Note that all custom analyzers defined in mappings will also be created. This is useful for search analyzers. Example:: from elasticsearch_dsl import analyzer, tokenizer my_analyzer = analyzer('my_analyzer', tokenizer=tokenizer('trigram', 'nGram', min_gram=3, max_gram=3), filter=['lowercase'] ) i = Index('blog') i.analyzer(my_analyzer) """

        analyzer = analysis.analyzer(*args, **kwargs)
        d = analyzer.get_analysis_definition()
        # empty custom analyzer, probably already defined out of our control
        if not d:
            return

        # merge the definition
        merge(self._analysis, d, True)