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12.5.4 Writer Implementations

Three implementations of the writer object interface are provided as examples by this module. Most applications will need to derive new writer classes from the `NullWriter` class.

`NullWriter` ()
  A writer which only provides the interface definition; no actions are taken on any methods. This should be the base class for all writers which do not need to inherit any implementation methods.

`AbstractWriter` ()
  A writer which can be used in debugging formatters, but not much else. Each method simply announces itself by printing its name and arguments on standard output.

`DumbWriter` ([file[, maxcol`= 72`]])
  Simple writer class which writes output on the file object passed in as file or, if file is omitted, on standard output. The output is simply word-wrapped to the number of columns specified by maxcol. This class is suitable for reflowing a sequence of paragraphs.