add get downloader tool

diff --git a/tools/get-pdf-downloader.py b/tools/get-pdf-downloader.py
new file mode 100755 (executable)
index 0000000..061f236
--- /dev/null
+++ b/tools/get-pdf-downloader.py
@@ -0,0 +1,13 @@
+#!/usr/bin/python3
+
+import os
+import sys
+from pypdf import PdfReader
+
+dir = sys.argv[-1]
+
+for f in os.listdir(dir):
+    filename = f.split(os.sep)[-1]
+    reader = PdfReader(dir + os.sep + f)
+    meta = reader.metadata
+    print(filename, ":", meta['/Downloader'])