[ENH] Shorten package import path from pytorch_forecasting to ptf

ptf/__init__.py

@@ -0,0 +1,25 @@
+from importlib.abc import MetaPathFinder
+import sys
+
+
+# Custom import interceptor to redirect all sub-imports
+# (e.g., ptf.models -> pytorch_forecasting.models)
+class LegacyRedirectFinder(MetaPathFinder):
+    def find_spec(self, fullname, path, target=None):
+        if fullname.startswith("ptf"):
+            real_name = fullname.replace("ptf", "pytorch_forecasting", 1)
+            try:
+                __import__(real_name)
+                sys.modules[fullname] = sys.modules[real_name]
+                return sys.modules[real_name].__spec__
+            except ImportError:
+                return None
+        return None
+
+
+sys.meta_path.insert(0, LegacyRedirectFinder())
+
+# Map the root package to pytorch_forecasting
+import pytorch_forecasting
+
+sys.modules["ptf"] = pytorch_forecasting

tests/test_ptf_import.py

@@ -0,0 +1,16 @@
+import sys
+
+
+def test_ptf_import_redirection():
+    # Clear any previous ptf imports from sys.modules
+    for module_name in list(sys.modules.keys()):
+        if module_name.startswith("ptf"):
+            del sys.modules[module_name]
+
+    # Import from ptf
+    import ptf.models as ptf_models
+    import pytorch_forecasting.models as pf_models
+
+    # Verify redirection and content equality
+    assert hasattr(ptf_models, "TemporalFusionTransformer")
+    assert ptf_models.TemporalFusionTransformer is pf_models.TemporalFusionTransformer