input: Write a function to create a doubly linked list in Python where each node can traverse to its previous and next nodes. Implement methods to append a node to the end, prepend a node to the beginning, and reverse the list.
  
  class Node:
      def __init__(self, data):
          self.data = data
          self.next = None
          self.prev = None
  
  class DoubleLinkedList:
      def __init__(self): 
          self.head = None
   
      def append(self, new_data): 
          new_node = Node(new_data) 
          if self.head is None:
              self.head =  new_node
          else: 
              curr_node = self.head
              while curr_node.next != None:
                  curr_node = curr_node.next
              curr_node.next = new_node
              new_node.prev = curr_node
   
      def prepend(self, new_data):
          new_node = Node(new_data) 
          if self.head is None: 
              self.head = new_node
              return
          new_node.next = self.head
          self.head.prev = new_node 
          self.head = new_node
  
      def reverse(self):
          curr_node = self.head
          while curr_node:
              temp = curr_node.next
              curr_node.next = curr_node.prev
              curr_node.prev = temp
              curr_node = curr_node.prev
          if temp:
              self.head = temp.prev
  
  # Test cases
  def test_linked_list():
      dll = DoubleLinkedList()
      dll.append(1)
      dll.append(2)
      dll.prepend(0)
      assert [0, 1, 2] == [dll.head.data, dll.head.next.data, dll.head.next.next.data]
      
      dll.reverse()
      assert [2, 1, 0] == [dll.head.data, dll.head.next.data, dll.head.next.next.data]
  
  test_linked_list()
output: 
  class Node:
      def __init__(self, data):
          self.data = data
          self.next = None
          self.prev = None
  
  class DoubleLinkedList:
      def __init__(self): 
          self.head = None
   
      def append(self, new_data): 
          new_node = Node(new_data) 
          if self.head is None:
              self.head =  new_node
          else: 
              curr_node = self.head
              while curr_node.next != None:
                  curr_node = curr_node.next
              curr_node.next = new_node
              new_node.prev = curr_node
   
      def prepend(self, new_data):
          new_node = Node(new_data) 
          if self.head is None: 
              self.head = new_node
              return
          new_node.next = self.head
          self.head.prev = new_node 
          self.head = new_node
  
      def reverse(self):
          curr_node = self.head
          while curr_node:
              temp = curr_node.next
              curr_node.next = curr_node.prev
              curr_node.prev = temp
              curr_node = curr_node.prev
          if temp:
              self.head = temp.prev
  