LangChain VCR Recording Setup (#1789)

* Tiktoken VCR fixture

* LangChain VCR Setup

* New test prompts for LangChain

* Record new responses

* Drop pin on aiohttp

---------

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: TimPansino

.gitignore

@@ -10,6 +10,9 @@ megalinter-reports/
 # Benchmarks
 .asv/
 
+# LLM Cache Files
+.tiktoken_cache
+
 # Byte-compiled / optimized / DLL files
 __pycache__/
 *.py[cod]

tests/mlmodel_langchain/_mock_external_openai_server.py

@@ -32,22 +32,22 @@ async def add_exclamation_async(message: str) -> str:
     return f"{message}!"
 
 
-@pytest.fixture(scope="session", params=["sync_tool", "async_tool"])
+@pytest.fixture(params=["sync_tool", "async_tool"])
 def tool_type(request):
     return request.param
 
 
-@pytest.fixture(scope="session")
+@pytest.fixture
 def tool_method_name(tool_type):
     return "run" if tool_type == "sync_tool" else "arun"
 
 
-@pytest.fixture(scope="session")
+@pytest.fixture
 def add_exclamation(tool_type, exercise_agent):
     if tool_type == "sync_tool":
         return add_exclamation_sync
     elif tool_type == "async_tool":
-        if exercise_agent._called_method in {"invoke", "stream"}:
+        if exercise_agent._called_method in ("invoke", "stream"):
             pytest.skip("Async tools cannot be invoked synchronously.")
         return add_exclamation_async
     else: