it outputs...

main.py

@@ -3,6 +3,7 @@ import cluster
 import config
 import pdfplumber
 from multiprocessing.pool import ThreadPool
+import pypdf
 import queue
 
 def main():
@@ -25,9 +26,15 @@ def de_column_ify():
                cropped_pages.append((got[0], got_i.path))
                #if got_i.chars:
                #   debug.debug_show(debug.debug_im(got_i.page))
-      cropped_pages = sorted(cropped_pages)
-      for cropped_page in cropped_pages:
-         print(cropped_page)
+
+   cropped_pages = sorted(cropped_pages)
+   writer = pypdf.PdfWriter()
+   for cropped_page in cropped_pages:
+      with open(cropped_page[1], "rb") as f:
+         reader = pypdf.PdfReader(f)
+         writer.add_page(reader.pages[0])
+   with open(config.INPUT + ".de_column_ified.pdf", "wb") as f:
+      writer.write(f)
 
 def de_columnify_page(q, path, page):
    result = cluster.Chars(path, page.chars, page).divide_into_columns()