chore: import upstream snapshot with attribution

python/semantic_kernel/prompt_template/input_variable.py

@@ -0,0 +1,26 @@
+# Copyright (c) Microsoft. All rights reserved.
+
+from typing import Any
+
+from semantic_kernel.kernel_pydantic import KernelBaseModel
+
+
+class InputVariable(KernelBaseModel):
+    """Input variable for a prompt template.
+
+    Args:
+        name: The name of the input variable.
+        description: The description of the input variable.
+        default: The default value of the input variable.
+        is_required: Whether the input variable is required.
+        json_schema: The JSON schema for the input variable.
+        allow_dangerously_set_content: Allow content without encoding, this controls
+            if this variable is encoded before use, default is False.
+    """
+
+    name: str
+    description: str | None = ""
+    default: Any | None = ""
+    is_required: bool | None = True
+    json_schema: str | None = ""
+    allow_dangerously_set_content: bool = False