Makefile uses python3

Author: dkogan

Makefile

@@ -3,16 +3,16 @@ all: README README.org
 # a multiple-target pattern rule means that a single invocation of the command
 # builds all the targets, which is what I want here
 %EADME %EADME.org: gnuplotlib.py README.footer.org extract_README.py
-	python extract_README.py gnuplotlib
+	python3 extract_README.py gnuplotlib
 
 # make distribution tarball
 dist:
-	python setup.py sdist
+	python3 setup.py sdist
 .PHONY: dist
 
 # make and upload the distribution tarball
 dist_upload:
-	python setup.py sdist upload
+	python3 setup.py sdist upload
 .PHONY: dist_upload
 
 clean: