diff --git a/ardumont/group_by_exception.py b/ardumont/group_by_exception.py
new file mode 100755
index 0000000..f4e39c7
--- /dev/null
+++ b/ardumont/group_by_exception.py
@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+
+# Copyright (C) 2017 the Software Heritage developers
+# License: GNU General Public License version 3, or any later version
+# See top-level LICENSE file for more information
+
+# Use:
+# ./kibana_fetch_logs.py | tee temporary-error-file | \
+#    ./group_by_exception.py > temporary-error-file-groupby-exception
+
+import ast
+import click
+import sys
+
+from collections import defaultdict
+
+
+def work_on_exception_msg(exception):
+    return exception[0:30]
+
+
+@click.command()
+@click.option('--file', help='File to read data from')
+def main(file):
+    group = defaultdict(list)
+
+    for line in sys.stdin:
+        line = line.strip()
+        data = ast.literal_eval(line)
+        reworked_exception_msg = work_on_exception_msg(data['exception'])
+        group[reworked_exception_msg].append(data['args'])
+
+    result = {}
+    for k, v in group.items():
+        result[k] = len(v)
+
+    print(result)
+
+
+if __name__ == '__main__':
+    main()