chore: import upstream snapshot with attribution

python/paddle/utils/lazy_import.py

@@ -0,0 +1,48 @@
+# Copyright (c) 2018 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed 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.
+"""Lazy imports for heavy dependencies."""
+
+from __future__ import annotations
+
+import importlib
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from types import ModuleType
+
+
+__all__ = []
+
+
+def try_import(module_name: str, err_msg: str | None = None) -> ModuleType:
+    """Try importing a module, with an informative error message on failure."""
+    install_name = module_name
+
+    if module_name.find('.') > -1:
+        install_name = module_name.split('.')[0]
+
+    if module_name == 'cv2':
+        install_name = 'opencv-python'
+
+    try:
+        mod = importlib.import_module(module_name)
+        return mod
+    except ImportError:
+        if err_msg is None:
+            err_msg = (
+                f"Failed importing {module_name}. This likely means that some paddle modules "
+                "require additional dependencies that have to be "
+                f"manually installed (usually with `pip install {install_name}`). "
+            )
+        raise ImportError(err_msg)