refactor: execute js/py code (#118)

tools/execute_py_code.py

@@ -1,6 +1,16 @@
+import io
+import sys
+
 def run(code: str):
     """Execute the python code.
     Args:
         code: Python code to execute, such as `print("hello world")`
     """
-    return eval(code)
+    old_stdout = sys.stdout
+    new_stdout = io.StringIO()
+    sys.stdout = new_stdout
+
+    exec(code)
+
+    sys.stdout = old_stdout
+    return new_stdout.getvalue()