Update difflib.py from 3.13.5 (#6067)

Lib/difflib.py

@@ -1200,6 +1200,25 @@ def context_diff(a, b, fromfile='', tofile='',
     strings for 'fromfile', 'tofile', 'fromfiledate', and 'tofiledate'.
     The modification times are normally expressed in the ISO 8601 format.
     If not specified, the strings default to blanks.
+
+    Example:
+
+    >>> print(''.join(context_diff('one\ntwo\nthree\nfour\n'.splitlines(True),
+    ...       'zero\none\ntree\nfour\n'.splitlines(True), 'Original', 'Current')),
+    ...       end="")
+    *** Original
+    --- Current
+    ***************
+    *** 1,4 ****
+      one
+    ! two
+    ! three
+      four
+    --- 1,4 ----
+    + zero
+      one
+    ! tree
+      four
     """
 
     _check_types(a, b, fromfile, tofile, fromfiledate, tofiledate, lineterm)
@@ -1609,7 +1628,7 @@ _file_template = """
 </html>"""
 
 _styles = """
-        table.diff {font-family:Courier; border:medium;}
+        table.diff {font-family: Menlo, Consolas, Monaco, Liberation Mono, Lucida Console, monospace; border:medium}
         .diff_header {background-color:#e0e0e0}
         td.diff_header {text-align:right}
         .diff_next {background-color:#c0c0c0}

Lib/test/test_difflib.py

@@ -186,6 +186,7 @@ just fits in two lineS yup!!
 the end"""
 
 class TestSFpatches(unittest.TestCase):
+
     def test_html_diff(self):
         # Check SF patch 914575 for generating HTML differences
         f1a = ((patch914575_from1 + '123\n'*10)*3)

Lib/test/test_difflib_expect.html

@@ -9,7 +9,7 @@
           content="text/html; charset=utf-8" />
     <title></title>
     <style type="text/css">
-        table.diff {font-family:Courier; border:medium;}
+        table.diff {font-family: Menlo, Consolas, Monaco, Liberation Mono, Lucida Console, monospace; border:medium}
         .diff_header {background-color:#e0e0e0}
         td.diff_header {text-align:right}
         .diff_next {background-color:#c0c0c0}