Created project 5

Project 5/Stack.py

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+######################################
+# DCS 229 -- Stack
+# Stack data structure implemented with Linked List
+# Date:
+# Name:
+# Resources Used:
+##########################################
+
+
+from LinkedList import *
+class EmptyError(Exception):
+    ''' class extending Exception to better document stack errors '''
+    def __init__(self, message: str):
+        self.message = message
+
+class Stack[T]:
+    ''' class to implement a stack ADT using our LinkedList class'''
+
+
+    def __init__(self):
+       
+        pass
+    def __len__(self) -> int:
+        ''' allows the len function to be called using an ArrayStack object, e.g.,
+               stack = ArrayStack()
+               print(len(stack))
+        Returns:
+            number of elements in the stack, as an integer
+        '''
+        pass
+
+    def push(self, item: T) -> None: 
+        ''' pushes a given item of arbitrary type onto the stack
+        Parameters:
+            item: an item of arbitrary type
+        Returns:
+            None
+        '''
+        pass
+
+    def pop(self) -> T:
+        ''' removes the topmost element from the stack and returns that element
+        Returns:
+            the topmost item, of arbitrary type
+        Raises:
+            EmptyError exception if the stack is empty
+        '''
+        pass
+
+    def peek(self) -> T:
+        ''' returns the topmost element from the stack without modifying the stack
+        Returns:
+            the topmost item, of arbitrary type
+        Raises:
+            EmptyError exception if the stack is empty
+        '''
+        pass
+
+    def is_empty(self) -> bool:
+        ''' indicates whether the stack is empty
+        Returns:
+            True if the stack is empty, False otherwise
+        '''
+        pass
+
+    def __str__(self) -> str:
+        ''' returns an str implementation of the Stack '''
+   
+        return str(self._data)
+
+def main():
+    # add your tests here!
+    pass
+
+if __name__ == "__main__":
+    main()
+