Courier pythonfilter pythonfilter is a framework for developing courierfilter programs in Python. The pythonfilter program itself is a multi-threaded daemon that loads filters as python modules and passes the control and data files from courier to each module in turn. pythonfilter includes several modules that provide utility functions. These modules are found in the "courier" directory. The "config" module provides functions to access or interpret Courier's configuration settings. The "control" module provides functions to interpret Courier's control files. pythonfilter is distributed under the GNU General Public License (GPL), as described in the COPYING file.