update init token setup

Author: atharvas

src/datasmith/__init__.py

@@ -1,6 +1,10 @@
 import os
+import sys
 
-with open("tokens.env", encoding="utf-8") as f:
-    lines = f.readlines()
-    tokens = {line.split("=")[0].strip(): line.split("=")[1].strip() for line in lines if "=" in line}
-os.environ.update(tokens)
+if os.path.exists("tokens.env"):
+    with open("tokens.env", encoding="utf-8") as f:
+        lines = f.readlines()
+        tokens = {line.split("=")[0].strip(): line.split("=")[1].strip() for line in lines if "=" in line}
+    os.environ.update(tokens)
+else:
+    sys.stderr.write("No tokens.env file found. Skipping environment variable setup.\n")