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class Solution:
	def mergeTwoLists(self, l1, l2):

	result = ListNode(0) # The new list we are going to eventually return
	head = result # keep a pointer to the head so we can return head.next in the end
	while(l1 != None and l2 != None): # This check is important in the case where one list is shorter than the other
		if l1.val < l2.val: # Add l1's value as a new node to result if its less than l2's
			result.next = ListNode(l1.val)
			l1 = l1.next
			result = result.next
		elif l2.val < l1.val: # Add l2's value as a new node to result if its less than l1's
			result.next = ListNode(l2.val)
			l2 = l2.next
			result = result.next
		else: # In this case, the values must be equal so add both to result and move the linked lists forward
			result.next = ListNode(l1.val)
			result = result.next
			result.next = ListNode(l2.val)
			result = result.next
			l1 = l1.next
			l2 = l2.next

	if l1 == None and l2 != None: # If l2 is longer than l1, add all of the remaining values of l2 to result
		while(l2 != None):
			result.next = ListNode(l2.val)
			result = result.next
			l2 = l2.next
	elif l2 == None and l1 != None: # if l1 is longer than l2, add all of the remaining values of l1 to result
		while(l1 != None):
			result.next = ListNode(l1.val)
			result = result.next
			l1 = l1.next

	return head.next # return the result