remove assert for 0 file size (#349)

* remove assert for 0 file size

* precommit fix

Author: mitali401

src/together/filemanager.py

@@ -73,8 +73,6 @@ def _get_file_size(
         if len(range_parts) == 2:
             total_size_in_bytes = int(range_parts[1])
 
-    assert total_size_in_bytes != 0, "Unable to retrieve remote file."
-
     return total_size_in_bytes
 
 
@@ -213,8 +211,6 @@ def download(
                 if not fetch_metadata:
                     file_size = int(response.headers.get("content-length", 0))
 
-                assert file_size != 0, "Unable to retrieve remote file."
-
                 with tqdm(
                     total=file_size,
                     unit="B",