Test on AppVeyor

.appveyor.yml

@@ -0,0 +1,29 @@
+version: build-{build}-{branch}
+
+environment:
+  matrix:
+    - PYTHON: "C:\\Python310"
+    - PYTHON: "C:\\Python39"
+    - PYTHON: "C:\\Python38"
+    - PYTHON: "C:\\Python37"
+    - PYTHON: "C:\\Python36"
+
+init:
+  - "echo %PYTHON%"
+
+install:
+#  - ps: |
+#      if (-not (Test-Path $env:PYTHON)) {
+#        curl -o install_python.ps1 https://raw.githubusercontent.com/matthew-brett/multibuild/11a389d78892cf90addac8f69433d5e22bfa422a/install_python.ps1
+#        .\install_python.ps1
+#      }
+  - ps: if (-not (Test-Path $env:PYTHON)) { throw "No $env:PYTHON" }
+  - "set PATH=%PYTHON%;%PYTHON%\\Scripts;%PATH%"
+  - python --version
+  - pip install -U virtualenv  # upgrade pip in tox's virtualenvs
+  - pip install tox
+
+build: off
+
+test_script:
+  - python test.py