add a PythonSDK (#327)

Author: moyanj

ecosystem.json

@@ -10,6 +10,7 @@
     { "type": "github", "repo": "iranee/qnap-alist-webdav" },
     { "type": "github", "repo": "yzbtdiy/alist_batch" },
     { "type": "github", "repo": "msterzhang/onelist" },
+    { "type": "github", "repo": "moyanj/AList3SDK" },
     { "type": "github", "repo": "lym12321/Alist-SDK" },
     { "type": "github", "repo": "power721/alist-tvbox" },
     { "type": "github", "repo": "everstu/Koolcenter_alist" },