diff --git a/pytchat/tool/block.py b/pytchat/tool/block.py
index 813e22a..14b8ece 100644
--- a/pytchat/tool/block.py
+++ b/pytchat/tool/block.py
@@ -7,7 +7,8 @@ class Block:
         index of this block on block list.
 
     first : int :
-        videoOffsetTimeMs of chat_data[0]
+        videoOffsetTimeMs of the first chat_data 
+        (chat_data[0])
         
     last : int :
         videoOffsetTimeMs of the last chat_data.
diff --git a/pytchat/tool/downloader.py b/pytchat/tool/downloader.py
index c187ca7..4cd363e 100644
--- a/pytchat/tool/downloader.py
+++ b/pytchat/tool/downloader.py
@@ -55,7 +55,6 @@ class Downloader:
         return (
             self.ready_blocks()
                 .remove_duplicate_head()
-#                .set_temporary_last()
                 .remove_overwrap()
                 .set_temporary_last()
                 .download_blocks()