Issue #25523: Correct "a" article to "an" article
This changes the main documentation, doc strings, source code comments, and a
couple error messages in the test suite. In some cases the word was removed
to fix the grammar.
diff --git a/Doc/library/os.path.rst b/Doc/library/os.path.rst
index 5d7edd1..99a36af 100644
--- a/Doc/library/os.path.rst
+++ b/Doc/library/os.path.rst
@@ -256,7 +256,7 @@
.. function:: samefile(path1, path2)
Return ``True`` if both pathname arguments refer to the same file or directory
- (as indicated by device number and i-node number). Raise an exception if a
+ (as indicated by device number and i-node number). Raise an exception if an
:func:`os.stat` call on either pathname fails.
Availability: Unix.