langchain/utilities/wikipedia.py/WikipediaAPIWrapper/run
class WikipediaAPIWrapper:    def run(self, query: str) -> str:
        """Run Wikipedia search and get page summaries."""
        page_titles = self.wiki_client.search(query[:WIKIPEDIA_MAX_QUERY_LENGTH])
        summaries = []
        for page_title in page_titles[: self.top_k_results]:
            if wiki_page := self._fetch_page(page_title):
                if summary := self._formatted_page_summary(page_title, wiki_page):
                    summaries.append(summary)
        if not summaries:
            return "No good Wikipedia Search Result was found"
        return "\n\n".join(summaries)[: self.doc_content_chars_max]