Add warning

Author: Diego Ardila

nucleus/dataset.py

@@ -30,6 +30,9 @@
 from .payload_constructor import construct_model_run_creation_payload
 
 
+WARN_FOR_LARGE_UPLOAD = 50000
+
+
 class Dataset:
     """
     Nucleus Dataset. You can append images with metadata to your dataset,
@@ -211,6 +214,11 @@ def append(
         """
         check_for_duplicate_reference_ids(dataset_items)
 
+        if len(dataset_items) > WARN_FOR_LARGE_UPLOAD and not asynchronous:
+            print(
+                "WARNING: for large uploads we recommend uploading your images remotely to a cloud storage provider and then using asynchronous=True."
+            )
+
         if asynchronous:
             check_all_paths_remote(dataset_items)
             request_id = serialize_and_write_to_presigned_url(