is a copy of head listnode can change the original listnode itslef?

class Solution(object):
def isPalindrome(self, head):

Si here i make a copy of the head

      temp1 = head
      temp2 = head
      temp3 = head
       x = head
   
   
    
if temp1 == None:
        return True
else:
        temp2 = temp1.next
        temp1.next == None

This is where i reverse the listnode

while temp2!= None:
        x = temp2.next
        temp2.next = temp1
        temp1 = temp2
        temp2 = x
        i=i+1

This is where I compare the original listnode(head) to the reversedlistnode

  while head!=None:
   print(str(temp1.val)+" "+str(head.val))
   if temp1.val != temp2.val:
       return False            
    temp1 = temp1.next
    head = head.next
    
          
    return True

when i try to run this if goes on an infinite loop it is a problem in leetcod(palindrom linked list) however what i want to know is if it alters the original listnode if i make a copy of the head hence the title. Can someone explaint it to me