scikit-learn · rth · Nov 4, 2019 · Nov 1, 2019 · Nov 1, 2019 · Nov 1, 2019
diff --git a/sklearn/_build_utils/deprecated_modules.py b/sklearn/_build_utils/deprecated_modules.py
@@ -270,14 +270,21 @@
 
 _FILE_CONTENT_TEMPLATE = """
 # THIS FILE WAS AUTOMATICALLY GENERATED BY deprecated_modules.py
-
-from .{new_module_name} import *  # noqa
+import sys
+from . i
8000
mport {new_module_name}
+from {relative_dots}externals._pep562 import Pep562
 from {relative_dots}utils.deprecation import _raise_dep_warning_if_not_pytest
 
 deprecated_path = '{deprecated_path}'
 correct_import_path = '{correct_import_path}'
 
 _raise_dep_warning_if_not_pytest(deprecated_path, correct_import_path)
+
+def __getattr__(name):
+    return getattr({new_module_name}, name)
+
+if not sys.version_info >= (3, 7):
+    Pep562(__name__)
 """
 
 

diff --git a/sklearn/externals/_pep562.py b/sklearn/externals/_pep562.py
@@ -0,0 +1,58 @@
+"""
+Backport of PEP 562.
+
+https://pypi.org/search/?q=pep562
+
+Licensed under MIT
+Copyright (c) 2018 Isaac Muse <isaacmuse@gmail.com>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
+and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+IN THE SOFTWARE.
+"""
+from __future__ import unicode_literals
+import sys
+
+__all__ = ('Pep562',)
+
+
+class Pep562(object):
+    """
+    Backport of PEP 562 <https://pypi.org/search/?q=pep562>.
+
+    Wraps the module in a class that exposes the mechanics to override `__dir__` and `__getattr__`.
+    The given module will be searched for overrides of `__dir__` and `__getattr__` and use them when needed.
+    """
+
+    def __init__(self, name):
+        """Acquire `__getattr__` and `__dir__`, but only replace module for versions less than Python 3.7."""
+
+        self._module = sys.modules[name]
+        self._get_attr = getattr(self._module, '__getattr__', None)
+        self._get_dir = getattr(self._module, '__dir__', None)
+        sys.modules[name] = self
+
+    def __dir__(self):
+        """Return the overridden `dir` if one was provided, else apply `dir` to the module."""
+
+        return self._get_dir() if self._get_dir else dir(self._module)
+
+    def __getattr__(self, name):
+        """Attempt to retrieve the attribute from the module, and if missing, use the overridden function if present."""
+
+        try:
+            return getattr(self._module, name)
+        except AttributeError:
+            if self._get_attr:
+                return self._get_attr(name)
+            raise
diff --git a/sklearn/tests/test_docstring_parameters.py b/sklearn/tests/test_docstring_parameters.py
@@ -16,6 +16,7 @@
 from sklearn.utils._testing import _get_func_name
 from sklearn.utils._testing import ignore_warnings
 from sklearn.utils.deprecation import _is_deprecated
+from sklearn.externals._pep562 import Pep562
 
 import pytest
 
@@ -145,6 +146,13 @@ def test_tabs():
 
         # because we don't import
         mod = importlib.import_module(modname)
+
+        # TODO: Remove when minimum python version is 3.7
+        # unwrap to get module because Pep562 backport wraps the original
+        # module
+        if isinstance(mod, Pep562):
+            mod = mod._module
+
         try:
             source = inspect.getsource(mod)
         except IOError:  # user probably should have run "make clean"