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chapter9.md

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+## Chapter 9: Text Summarization
+LangChain can be used to efficiently summarize long pieces of text.
+
+```
+from langchain.chains.summarize import load_summarize_chain
+from langchain.llms import OpenAI
+from langchain.docstore.document import Document
+
+
+text = """
+LangChain is a framework for developing applications powered by language models. It enables applications that:
+Are context-aware: connect a language model to sources of context (prompt instructions, few shot examples, content to ground its response in, etc.)
+Reason: rely on a language model to reason (about how to answer based on provided context, what actions to take, etc.)
+"""
+
+
+docs = [Document(page_content=text)]
+
+
+chain = load_summarize_chain(OpenAI(temperature=0), chain_type="stuff")
+
+
+print(chain.run(docs))
+```