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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 search_extension(self, limit=100, offset=0, **kw):
 """Search the list of available extensions."""


        response = self.request(E.searchExtensionRequest(
            E.limit(limit),
            E.offset(offset),
            E.withDescription(int(kw.get('with_description', 0))),
            E.withPrice(int(kw.get('with_price', 0))),
            E.withUsageCount(int(kw.get('with_usage_count', 0))),
        ))
        return response.as_models(Extension)