1 files changed, 33 insertions, 0 deletions
diff --git a/azure/aria/aria-extension-cloudify/src/aria/extensions/aria_extension_tosca/simple_v1_0/presentation/extensible.py b/azure/aria/aria-extension-cloudify/src/aria/extensions/aria_extension_tosca/simple_v1_0/presentation/extensible.py
new file mode 100644
index 0000000..0e3c94d
--- /dev/null
+++ b/azure/aria/aria-extension-cloudify/src/aria/extensions/aria_extension_tosca/simple_v1_0/presentation/extensible.py
@@ -0,0 +1,33 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from aria.utils.caching import cachedmethod
+from aria.parser.presentation import (Presentation, has_fields, primitive_dict_field)
+
+
+@has_fields
+class ExtensiblePresentation(Presentation):
+    """
+    A presentation that supports an optional ``_extensions`` dict field.
+    """
+
+    @primitive_dict_field()
+    def _extensions(self):
+        pass
+
+    @cachedmethod
+    def _get_extension(self, name, default=None):
+        extensions = self._extensions
+        return extensions.get(name, default) if extensions is not None else None # pylint: disable=no-member