Yurttas/PL/SL/python/docs/core-python-programming/doc/16/lib/formatter-impls.html
12.5.2 Formatter Implementations
Two implementations of formatter objects are provided by this module. Most applications may use one of these classes without modification or subclassing.
- NullFormatter ([writer])
- A formatter which does nothing. If writer is omitted, a NullWriter instance is created. No methods of the writer are called by NullFormatter instances. Implementations should inherit from this class if implementing a writer interface but don't need to inherit any implementation.
- AbstractFormatter (writer)
- The standard formatter. This implementation has demonstrated wide applicability to many writers, and may be used directly in most circumstances. It has been used to implement a full-featured world-wide web browser.