diff --git a/ufpy/ustack.py b/ufpy/ustack.py
deleted file mode 100644
index b1dddec..0000000
--- a/ufpy/ustack.py
+++ /dev/null
@@ -1,80 +0,0 @@
-# -*- encodibg: utf-8 -*-
-from __future__ import annotations
-from typing import Any
-
-class UStackElement():
-    def __init__(self, value: Any) -> UStackElement:
-        """
-        UStackElement is using like an element in UStack.
-        """
-        self.__value: Any = value
-        
-    def __len__(self):
-        return len(self.__value)
-        
-    def __str__(self):
-        return str(self.__value)
-        
-    def __int__(self):
-        return int(self.__value)
-        
-    def __bool__(self):
-        return bool(self.__value)
-
-    def __dict__(self):
-        return dict(self.__value)
-        
-    def __bytes__(self, encoding: str = 'utf-8'):
-        return bytes(self.__value, encoding)
-
-class UStack():
-    def __init__(self, _list: list | tuple = list()) -> UStack:
-        """
-        UStack's methods:
-            append(**items) - to add item to begin.
-            empty() - true if stack is empty.
-            pop() - delete the last element in stack.
-        """
-        if len(_list) != 0:
-            self.__list = [UStackElement(item) for item in _list]
-        else:
-            self.__list = _list
-        
-    def append(self, *items) -> UStackElement:
-        for item in items:
-            item = UStackElement(item)
-            self.__list.append(item)
-        return items
-        
-    def empty(self) -> bool:
-        return len(self.__list) == 0
-        
-    def pop(self) -> UStackElement | None:
-        if not self.empty():
-            item: UStackElement = self.__list[-1]
-            del self.__list[-1]
-            return item
-        else:
-            return None
-        
-    def top(self) -> UStackElement | None:
-        if not self.empty():
-            return self.__list[-1]
-        else:
-            return None
-
-    def __add__(self, stack: UStack) -> UStack:
-        return UStack(self.__list + stack.__list)
-
-    def __radd__(self, stack: UStack) -> UStack:
-        return UStack(stack.__list + self.__list)
-    
-    def __len__(self) -> int:
-        return len(self.__list)
-
-s = UStack()
-s.append(1, 2, 3, 4, 6)
-s2 = UStack()
-s2.append(1, 2, 3, 4, 5)
-s3 = s + s2
-print(s3.top())
\ No newline at end of file