diff --git a/lang/python/Makefile.am b/lang/python/Makefile.am
index 1d7aee8b..ea37da97 100644
--- a/lang/python/Makefile.am
+++ b/lang/python/Makefile.am
@@ -65,6 +65,9 @@ dist/pyme3-$(VERSION).tar.gz dist/pyme3-$(VERSION).tar.gz.asc: copystamp
 	  $(PYTHON) setup.py sdist --verbose
 	gpg2 --detach-sign --armor dist/pyme3-$(VERSION).tar.gz
 
+.PHONY: prepare
+prepare: copystamp
+
 .PHONY: sdist
 sdist: dist/pyme3-$(VERSION).tar.gz dist/pyme3-$(VERSION).tar.gz.asc