Fix copy pasted docs and snake_case files

telethon/tl/custom/__init__.py

@@ -1,6 +1,6 @@
 from .draft import Draft
 from .dialog import Dialog
-from .input_sized_file import InputSizedFile
+from .inputsizedfile import InputSizedFile
 from .messagebutton import MessageButton
 from .forward import Forward
 from .message import Message

telethon/tl/custom/messagebutton.py

@@ -5,9 +5,9 @@ import webbrowser
 
 class MessageButton:
     """
-    Custom class that encapsulates a message providing an abstraction to
-    easily access some commonly needed features (such as the markdown text
-    or the text for a given message entity).
+    Custom class that encapsulates a message button providing
+    an abstraction to easily access some commonly needed features
+    (such as clicking the button itself).
 
     Attributes: