Add example for converting SPDX 2 to 3

Signed-off-by: Holger Frydrych <holger.frydrych@tngtech.com>

Author: fholger

examples/spdx2_convert_to_spdx3.py

@@ -0,0 +1,21 @@
+#  SPDX-FileCopyrightText: 2023 spdx contributors
+#
+#  SPDX-License-Identifier: Apache-2.0
+from os import path
+
+from spdx_tools.spdx3.writer.json_ld.json_ld_writer import write_payload
+
+from spdx_tools.spdx3.bump_from_spdx2.spdx_document import bump_spdx_document
+
+from spdx_tools.spdx.parser.parse_anything import parse_file
+
+# This example demonstrates how to load an existing SPDX2 file and convert it to the SPDX3 format
+
+# Provide a path to the input file
+input_path = path.join(path.dirname(__file__), "..", "tests", "spdx", "data", "SPDXLite.spdx")
+# Parse the original SPDX2 input file
+spdx2_document = parse_file(input_path)
+# Convert original document to an SPDX3 payload
+spdx3_payload = bump_spdx_document(spdx2_document)
+# Write SPDX3 payload in json-ld format
+write_payload(spdx3_payload, "spdx2_to_3.json")