While using new_list = my_list, any modifications to new_list changes my_list every time. Why is this, and how can I clone or copy the list to prevent it?

When you use the assignment operator ` = ` to assign a new list to a variable , it creates a new reference to the original list . This means that any changes made to the new list will also affect the original list . To prevent this from happening , you can use the ` copy () ` method to create a copy of the original list . \n \n Here ' s an example : \n `` ` python \n my _ list = [ 1 , 2 , 3 ] \n new _ list = my _ list \n \n # mod ifying new _ list will also modify my _ list \n new _ list [ 0 ] = 4 \n print ( my _ list ) # Output : [ 4 , 2 , 3 ] \n \n # creating a copy of my _ list \n new _ list = my _ list . copy () \n \n # mod ifying new _ list will not affect my _ list \n new _ list [ 0 ] = 5 \n print ( my _ list ) # Output : [ 1 , 2 , 3 ] \n `` ` \n In this example , ` my _ list ` is the original list , and ` new _ list ` is a reference to the original list . When ` new _ list ` is assigned to ` my _ list `, it creates a new reference to the original list . When ` new _ list ` is modified , it also mod ifies the original list . \n \n To create a copy of the original list , we use the ` copy () ` method , which returns a new list that is a copy of the original list . When we assign ` new _ list ` to ` my _ list `, it creates a new reference to the original list , but any changes made to ` new _ list ` will not affect the original list . </s>