Update openai.md (#214)

* Update openai.md

The example was wrong. corrected it

* fix example

* fix

---------

Co-authored-by: anakin87 <[email protected]>

integrations/openai.md

@@ -83,6 +83,13 @@ from haystack.utils import Secret
 from haystack.components.retrievers.in_memory import InMemoryBM25Retriever
 from haystack.components.builders.prompt_builder import PromptBuilder
 from haystack.components.generators import OpenAIGenerator
+from haystack.document_stores.in_memory import InMemoryDocumentStore
+from haystack import Document
+
+docstore = InMemoryDocumentStore()
+docstore.write_documents([Document(content="Rome is the capital of Italy"), Document(content="Paris is the capital of France")])
+
+query = "What is the capital of France?"
 
 template = """
 Given the following information, answer the question.
@@ -92,21 +99,26 @@ Context:
     {{ document.content }}
 {% endfor %}
 
-Question: What's the official language of {{ country }}?
+Question: {{ query }}?
 """
 pipe = Pipeline()
 
-pipe.add_component("retriever", InMemoryBM25Retriever(document_store=document_store))
+pipe.add_component("retriever", InMemoryBM25Retriever(document_store=docstore))
 pipe.add_component("prompt_builder", PromptBuilder(template=template))
-pipe.add_component("llm", OpenAIGenerator(model="gpt-4", api_key=Secret.from_token("YOUR_OPENAI_API_KEY")))
+pipe.add_component("llm", OpenAIGenerator(api_key=Secret.from_token("YOUR_OPENAI_API_KEY"))
 pipe.connect("retriever", "prompt_builder.documents")
 pipe.connect("prompt_builder", "llm")
 
-pipe.run({
+res=pipe.run({
     "prompt_builder": {
-        "country": "France"
+        "query": query
+    },
+    "retriever": {
+        "query": query
     }
-})   
+})
+
+print(res)   
 ```
 
 #### Transcriber Models