[3.12] gh-71261: Add paragraph on shadowing submodules with star impo…

…rts (GH-107004) (#107100)

Co-authored-by: wulmer <wulmer@users.noreply.github.com>

Doc/tutorial/modules.rst

@@ -512,6 +512,22 @@ code::
 This would mean that ``from sound.effects import *`` would import the three
 named submodules of the :mod:`sound.effects` package.
 
+Be aware that submodules might become shadowed by locally defined names. For
+example, if you added a ``reverse`` function to the
+:file:`sound/effects/__init__.py` file, the ``from sound.effects import *``
+would only import the two submodules ``echo`` and ``surround``, but *not* the
+``reverse`` submodule, because it is shadowed by the locally defined
+``reverse`` function::
+
+ __all__ = [
+ "echo", # refers to the 'echo.py' file
+ "surround", # refers to the 'surround.py' file
+ "reverse", # !!! refers to the 'reverse' function now !!!
+ ]
+
+ def reverse(msg: str): # <-- this name shadows the 'reverse.py' submodule
+ return msg[::-1] # in the case of a 'from sound.effects import *'
+
 If ``__all__`` is not defined, the statement ``from sound.effects import *``
 does *not* import all submodules from the package :mod:`sound.effects` into the
 current namespace; it only ensures that the package :mod:`sound.effects` has