kill reference to default encoding #6889

Doc/howto/unicode.rst

@@ -150,9 +150,8 @@ Generally people don't use this encoding, instead choosing other encodings that
 are more efficient and convenient.
 
 Encodings don't have to handle every possible Unicode character, and most
-encodings don't.  For example, Python's default encoding is the 'ascii'
-encoding.  The rules for converting a Unicode string into the ASCII encoding are
-simple; for each code point:
+encodings don't.  The rules for converting a Unicode string into the ASCII
+encoding, for example, are simple; for each code point:
 
 1. If the code point is < 128, each byte is the same as the value of the code
    point.