This is a port of MMTK (Molecular Modeling ToolKit). In addition to providing ready-to-use implementations of standard algorithms, MMTK serves as a code basis that can be easily extended and modified to deal with standard and non-standard problems in molecular simulations. MMTK consists of nothing more than a collection of Python modules, most of which written in Python itself, with only a small time-critical part (e.g. energy evaluation) written in C. MMTK applications are Python programs that make use of these modules.