Assume the following class implements the STACK abstract data type (ADT) using the array ADT.

class aStack(iArray):

def __init__(self, capacity = 5):

self._items = iArray(capacity)

self._top = -1

self._size = 0

def push(self, newItem):

self._top += 1

self._size += 1

self._items[self._top] = newItem

def pop(self):

oldItem = self._items[self._top]

self._items[self._top] = None

self._top -= 1

self._size -= 1

return oldItem

def peek(self):

return self._items[self._top]

def __len__(self):

return self._size

def __str__(self):

result = ' '

for i in range(len(self)):

result += str(self._items[i]) + ' '

return result

A- Emulate the stack behavior using the Python list data structure rather than the Arrary ADT.

B- Redefine the Stack class methods to push and pop two items rather than one item at a time.

For example, if the stack includes numbers from one to ten: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10], then invoking the pop() method twice will remove the last four elements and modify the stack elements to be: [1, 2, 3, 4, 5, 6].

C- Define and implement a function that reverses the items of a given stack using only the methods defined in the Stack class.

For example, if the stack includes the elements from one to ten: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10], then calling the new function will modify the stack elements to be from ten to one: [10, 9, 8, 7, 6, 5, 4, 3, 2, 1].