diff --git a/sqlite_utils/utils.py b/sqlite_utils/utils.py
index 29440a5..9e9882a 100644
--- a/sqlite_utils/utils.py
+++ b/sqlite_utils/utils.py
@@ -304,10 +304,7 @@ def rows_from_file(
         rows = rows_from_file(
             fp, format=Format.CSV, dialect=csv.excel_tab, encoding=encoding
         )[0]
-        return (
-            _extra_key_strategy(rows, ignore_extras, extras_key),
-            Format.TSV,
-        )
+        return _extra_key_strategy(rows, ignore_extras, extras_key), Format.TSV
     elif format is None:
         # Detect the format, then call this recursively
         buffered = io.BufferedReader(cast(io.RawIOBase, fp), buffer_size=4096)