A keyword list of four thousand terms comes back from deduplication at 3,900. It still contains hundreds of duplicates, because exact-match deduplication only catches identical strings and search intent does not care about word order.
The duplicates hiding in plain sight
cheap flights to paris, flights to paris cheap and paris flights cheap are three rows in the export and one search intent. Build content plans from the raw list and you will commission three briefs for the same page.
Collapsing them
Sort the words inside each line, then run an exact deduplication over the result. Every permutation of the same word set collapses to one row, and the true size of the list appears — often noticeably smaller than the tool that generated it claimed.
Use the count, keep the originals
Work from the collapsed list to decide how many pages you need. Go back to the original phrasing when writing them — real people search in natural word order, and the alphabetised version is a counting device, not copy.
Try it: Alphabetize Words Within Each Line on SeoWolf's Notepad.