Cadlabs/python tool sanitization (#4754)

Co-authored-by: BenSchZA <BenSchZA@users.noreply.github.com>

langchain/tools/python/tool.py

@@ -19,6 +19,17 @@ def _get_default_python_repl() -> PythonREPL:
     return PythonREPL(_globals=globals(), _locals=None)
 
 
+_MD_PY_BLOCK = "```python"
+
+
+def sanitize_input(query: str) -> str:
+    query = query.strip()
+    if query[: len(_MD_PY_BLOCK)] == _MD_PY_BLOCK:
+        query = query[len(_MD_PY_BLOCK) :].strip()
+    query = query.strip("`").strip()
+    return query
+
+
 class PythonREPLTool(BaseTool):
     """A tool for running python code in a REPL."""
 
@@ -39,7 +50,7 @@ class PythonREPLTool(BaseTool):
     ) -> Any:
         """Use the tool."""
         if self.sanitize_input:
-            query = query.strip().strip("```")
+            query = sanitize_input(query)
         return self.python_repl.run(query)
 
     async def _arun(
@@ -84,8 +95,7 @@ class PythonAstREPLTool(BaseTool):
         """Use the tool."""
         try:
             if self.sanitize_input:
-                # Remove the triple backticks from the query.
-                query = query.strip().strip("```")
+                query = sanitize_input(query)
             tree = ast.parse(query)
             module = ast.Module(tree.body[:-1], type_ignores=[])
             exec(ast.unparse(module), self.globals, self.locals)  # type: ignore

tests/unit_tests/tools/python/test_python.py

@@ -3,7 +3,11 @@ import sys
 
 import pytest
 
-from langchain.tools.python.tool import PythonAstREPLTool, PythonREPLTool
+from langchain.tools.python.tool import (
+    PythonAstREPLTool,
+    PythonREPLTool,
+    sanitize_input,
+)
 
 
 def test_python_repl_tool_single_input() -> None:
@@ -21,3 +25,30 @@ def test_python_ast_repl_tool_single_input() -> None:
     tool = PythonAstREPLTool()
     assert tool.is_single_input
     assert tool.run("1 + 1") == 2
+
+
+def test_sanitize_input() -> None:
+    query = """
+    ```
+        p = 5
+    ```
+    """
+    expected = "p = 5"
+    actual = sanitize_input(query)
+    assert expected == actual
+
+    query = """
+       ```python
+        p = 5
+    ```
+    """
+    expected = "p = 5"
+    actual = sanitize_input(query)
+    assert expected == actual
+
+    query = """
+    p = 5
+    """
+    expected = "p = 5"
+    actual = sanitize_input(query)
+    assert expected == actual