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diff --git a/doc/examples/action.py b/doc/examples/action.py
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+#!/usr/bin/python3
+#
+# LOW LEVEL example how to deal with the depcache
+#
+# you probably do not want to use this low level code and use
+# the high level "apt" interface instead that can do all this
+# but with a nicer API
+
+import apt_pkg
+from progress import TextFetchProgress
+
+from apt.progress.text import OpProgress
+
+# init
+apt_pkg.init()
+
+progress = OpProgress()
+cache = apt_pkg.Cache(progress)
+print("Available packages: %s " % cache.package_count)
+
+print("Fetching")
+progress = TextFetchProgress()
+source = apt_pkg.SourceList()
+cache.update(progress, source)
+
+iter = cache["base-config"]
+print("example package iter: %s" % iter)
+
+# get depcache
+print("\n\n depcache")
+depcache = apt_pkg.DepCache(cache)
+depcache.read_pinfile()
+print("got a depcache: %s " % depcache)
+print("Marked for install: %s " % depcache.inst_count)
+
+print("\n\n Reinit")
+depcache.init(progress)
+
+# sys.exit()
+
+# get a canidate version
+ver = depcache.get_candidate_ver(iter)
+print("Candidate version: %s " % ver)
+
+print("\n\nQuerry interface")
+print(f"{iter.name}.is_upgradable(): {depcache.is_upgradable(iter)}")
+
+print("\nMarking interface")
+print("Marking '%s' for install" % iter.name)
+depcache.mark_install(iter)
+print("Install count: %s " % depcache.inst_count)
+print(f"{iter.name}.marked_install(): {depcache.marked_install(iter)}")
+print(f"{iter.name}.marked_upgrade(): {depcache.marked_upgrade(iter)}")
+print(f"{iter.name}.marked_delete(): {depcache.marked_delete(iter)}")
+
+print("Marking %s for delete" % iter.name)
+depcache.mark_delete(iter)
+print("del_count: %s " % depcache.del_count)
+print(f"{iter.name}.marked_delete(): {depcache.marked_delete(iter)}")
+
+iter = cache["apt"]
+print("\nMarking '%s' for install" % iter.name)
+depcache.mark_install(iter)
+print("Install count: %s " % depcache.inst_count)
+print(f"{iter.name}.marked_install(): {depcache.marked_install(iter)}")
+print(f"{iter.name}.marked_upgrade(): {depcache.marked_upgrade(iter)}")
+print(f"{iter.name}.marked_delete(): {depcache.marked_delete(iter)}")
+
+print("Marking %s for keep" % iter.name)
+depcache.mark_keep(iter)
+print("Install: %s " % depcache.inst_count)
+
+iter = cache["python-apt"]
+print("\nMarking '%s' for install" % iter.name)
+depcache.mark_install(iter)
+print("Install: %s " % depcache.inst_count)
+print("Broken count: %s" % depcache.broken_count)
+print("fix_broken() ")
+depcache.fix_broken()
+print("Broken count: %s" % depcache.broken_count)
+
+print("\nPerforming upgrade")
+depcache.upgrade()
+print("Keep: %s " % depcache.keep_count)
+print("Install: %s " % depcache.inst_count)
+print("Delete: %s " % depcache.del_count)
+print("usr_size: %s " % apt_pkg.size_to_str(depcache.usr_size))
+print("deb_size: %s " % apt_pkg.size_to_str(depcache.deb_size))
+
+for pkg in cache.packages:
+    if (
+        pkg.current_ver is not None
+        and not depcache.marked_install(pkg)
+        and depcache.is_upgradable(pkg)
+    ):
+        print("upgrade didn't upgrade (kept): %s" % pkg.name)
+
+print("\nPerforming Distupgrade")
+depcache.upgrade(True)
+print("Keep: %s " % depcache.keep_count)
+print("Install: %s " % depcache.inst_count)
+print("Delete: %s " % depcache.del_count)
+print("usr_size: %s " % apt_pkg.size_to_str(depcache.usr_size))
+print("deb_size: %s " % apt_pkg.size_to_str(depcache.deb_size))
+
+# overview about what would happen
+for pkg in cache.packages:
+    if depcache.marked_install(pkg):
+        if pkg.current_ver is not None:
+            print("Marked upgrade: %s " % pkg.name)
+        else:
+            print("Marked install: %s" % pkg.name)
+    elif depcache.marked_delete(pkg):
+        print("Marked delete: %s" % pkg.name)
+    elif depcache.marked_keep(pkg):
+        print("Marked keep: %s" % pkg.name)