These modules are not normally available for import; additional
work must be done to make them available.
These extension modules written in C are not built by default.
Under Unix, these must be enabled by
uncommenting the appropriate lines in Modules/Setup in the build tree and either rebuilding
Python if the modules are statically linked, or building and
installing the shared object if using dynamically-loaded
extensions.
- timing
-- Measure time intervals to high resolution (use time.clock() instead).