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4.5.5.1 Filter Methods

`pass_on`()
  Passes all data through the filter without any processing.

`read`([length])
  Reads at most len bytes from the next filter, returning a string with the data read or None if End Of Stream (EOS) has been reached. A filter must be closed once the EOS has been encountered.

  If the len argument is negative or omitted, reads all data currently available.

`readline`([length])
  Reads a line from the next filter or up to length bytes.

`write`(string)
  Writes string to the next filter.

`flush`()
  Flushes the output by sending a FLUSH bucket.

`close`()
  Closes the filter and sends an EOS bucket. Any further IO operations on this filter will throw an exception.

`disable`()
  Tells mod_python to ignore the provided handler and just pass the data on. Used internally by mod_python to print traceback from exceptions encountered in filter handlers to avoid an infinite loop.