make supports custom python interpreter

Makefile

@@ -1,17 +1,19 @@
+PYTHON = python
+
 # This .PHONY line prevents make from treating the docs/ directory like a build
 # product:
 .PHONY: docs
 
 coverage:
-	coveralls -v
+	$(PYTHON) -m coveralls -v
 
 docs:
 	$(MAKE) -C docs html
 
 test:
-	pytest --cov=trio_websocket
+	$(PYTHON) -m pytest --cov=trio_websocket
 
 publish:
-	python setup.py sdist
+	$(PYTHON) setup.py sdist
 	twine upload dist/*
 	rm -fr build dist .egg trio_websocket.egg-info

docs/Makefile

@@ -2,8 +2,9 @@
 #
 
 # You can set these variables from the command line.
+PYTHON        = python
 SPHINXOPTS    =
-SPHINXBUILD   = sphinx-build
+SPHINXBUILD   = $(PYTHON) -m sphinx
 SOURCEDIR     = .
 BUILDDIR      = _build
 
@@ -16,4 +17,4 @@ help:
 # Catch-all target: route all unknown targets to Sphinx using the new
 # "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
 %: Makefile
-	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)