Issue #25523: Backported a-to-an corrections.
diff --git a/Doc/library/email.parser.rst b/Doc/library/email.parser.rst
index 0f99a2f..04e2334 100644
--- a/Doc/library/email.parser.rst
+++ b/Doc/library/email.parser.rst
@@ -133,7 +133,7 @@
methods on file-like objects.
The text contained in *fp* must be formatted as a block of :rfc:`2822`
- style headers and header continuation lines, optionally preceded by a
+ style headers and header continuation lines, optionally preceded by an
envelope header. The header block is terminated either by the end of the
data or by a blank line. Following the header block is the body of the
message (which may contain MIME-encoded subparts).