Move a specific occurrence to end of linked list in python

Python program for Move a specific occurrence to end of linked list. Here problem description and explanation.

#  Python 3 program for
#  Move given occurrence to the end of linked list

#  Linked list node
class LinkNode :
	def __init__(self, data) :
		self.data = data
		self.next = None
	

class SingleLL :
	def __init__(self) :
		self.head = None
	
	#  Add new node at the end of linked list
	def insert(self, value) :
		#  Create a node
		node = LinkNode(value)
		if (self.head == None) :
			self.head = node
		else :
			temp = self.head
			#  Find last node
			while (temp.next != None) :
				#  Visit to next node
				temp = temp.next
			
			#  Add node at last position
			temp.next = node
		
	
	#  Display all Linked List elements
	def display(self) :
		if (self.head != None) :
			temp = self.head
			while (temp != None) :
				#  Display node value
				print("  ", temp.data, end = "")
				#  Visit to next node
				temp = temp.next
			
		else :
			print("Empty Linked list")
		
	
	#  Move all occurrence of given element into the 
	#  end of linked list position
	def moveNodes(self, element) :
		if (self.head == None) :
			print("Empty linked list")
		else :
			#  Some useful auxiliary variables
			temp = self.head
			prev = None
			nodes = None
			current = None
			#  Move a particular occurrence to end of linked list
			while (temp != None) :
				current = temp
				#  Visit to next node
				temp = temp.next
				if (current.data == element) :
					#  Find move element
					if (self.head == current) :
						#  Move the front node element 
						#  to the end position
						self.head = temp
					
					if (prev != None) :
						#  When have a intermediate node
						#  Unlink the move node
						prev.next = temp
					
					current.next = nodes
					nodes = current
				else :
					prev = current
				
			
			if (self.head == None and nodes != None) :
				#  All same nodes are exist in linked list
				self.head = nodes
			elif (prev != None and nodes != None) :
				#  Add occurrence to end
				prev.next = nodes
			else :
				#  When given occurrences element are not found
				print("Occurrences element are not found : ", element)
			
		
	

def main() :
	sll = SingleLL()
	#  Linked list
	#  1 → 2 → 3 → 4 → 4 → 5 → 6 → 7 → NULL
	sll.insert(7)
	sll.insert(1)
	sll.insert(2)
	sll.insert(7)
	sll.insert(3)
	sll.insert(2)
	sll.insert(7)
	occurrence = 7
	print("Before move occurrence ", occurrence ," to end")
	# display all node
	sll.display()
	print("\nAfter move occurrence ", occurrence ," to end")
	sll.moveNodes(occurrence)
	sll.display()

if __name__ == "__main__": main()

Output

Before move occurrence  7  to end
   7   1   2   7   3   2   7
After move occurrence  7  to end
   1   2   3   2   7   7   7