Remove duplicates from sorted doubly linked list in python

Python program for Remove duplicates from sorted doubly linked list. Here problem description and explanation.

#  Python 3 program for
#  Remove duplicates from sorted doubly linked list 
class LinkNode :
	def __init__(self, data) :
		self.data = data
		self.next = None
		self.prev = None
	

class DoublyLinkedList :
	def __init__(self) :
		self.head = None
	
	#  Insert new node at end position
	def insert(self, value) :
		#  Create a node
		node = LinkNode(value)
		if (self.head == None) :
			#  Add first node
			self.head = node
			return
		
		temp = self.head
		#  Find last node
		while (temp.next != None) :
			#  Visit to next node
			temp = temp.next
		
		#  Add node at the end position
		temp.next = node
		node.prev = temp
	
	#  Display node element of doubly linked list
	def display(self) :
		if (self.head == None) :
			print("Empty Linked List")
		else :
			print("Doubly Linked List Element :", end = "")
			#  Get first node of linked list
			temp = self.head
			#  iterate linked list 
			while (temp != None) :
				#  Display node value
				print(" ", temp.data, end = " ")
				#  Visit to next node
				temp = temp.next
			
		
	
	#  Delete duplicates from doubly linked list 
	def removeNode(self) :
		if (self.head != None) :
			find = None
			#  Get second node
			node = self.head.next
			#  Iterating linked list and remove duplicate nodes
			while (node != None) :
				#  Duplicate nodes
				if (node.prev.data == node.data) :
					#  When we are gets a similar node
					find = node
				
				#  Visit to next node
				node = node.next
				if (find != None) :
					#  Rebuild the connection of before and 
					#  after deleted node.
					if (find.prev != None) :
						#  When previous node exists
						find.prev.next = node
					
					if (node != None) :
						#  When next node exists
						node.prev = find.prev
					
					#  Unlink
					#  remove element
					find.prev = None
					find.next = None
					find = None
				
			
		
	

def main() :
	dll = DoublyLinkedList()
	#  Insert following linked list nodes
	dll.insert(5)
	dll.insert(5)
	dll.insert(7)
	dll.insert(9)
	dll.insert(9)
	dll.insert(9)
	dll.insert(11)
	dll.insert(45)
	dll.insert(45)
	print("Before delete duplicates ")
	#  Display all node
	dll.display()
	print("\nAfter delete duplicates ")
	dll.removeNode()
	dll.display()

if __name__ == "__main__": main()

Output

Before delete duplicates
Doubly Linked List Element :  5   5   7   9   9   9   11   45   45
After delete duplicates
Doubly Linked List Element :  5   7   9   11   45