What is the process for selecting items in a list that appear only once?

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Create a list of items: Start by creating a list of all the items that need to be checked for duplicates.

Count the occurrence of each item: Next, count the occurrence of each item in the list. This can be done by iterating through the list and keeping track of the count of each item.

Filter out items that appear more than once: Finally, filter out any items that appear more than once. This can be done by iterating through the list again and only including items that have a count of 1.

Return the filtered list: Once all duplicate items have been filtered out, return the resulting list of items that appear only once.