Defines the interface for stateless encoders/decoders.
The .encode()/.decode() methods may use different error
handling schemes by providing the errors argument. These
string values are predefined:
'strict' - raise a ValueError error (or a subclass)
'ignore' - ignore the character and continue with the next
'replace' - replace with a suitable replacement character;
Python will use the official U+FFFD REPLACEMENT
CHARACTER for the builtin Unicode codecs on
decoding and '?' on encoding.
'surrogateescape' - replace with private code points U+DCnn.
'xmlcharrefreplace' - Replace with the appropriate XML
character reference (only for encoding).
'backslashreplace' - Replace with backslashed escape sequences.
'namereplace' - Replace with \N{...} escape sequences
(only for encoding).
The set of allowed values can be extended via register_error.