PyQt is a set of Python v2 and v3 bindings for Digia's Qt application framework and runs on all platforms supported by Qt including Windows, MacOS/X and Linux. PyQt5 supports Qt v5. PyQt4 supports Qt v4 and will build against Qt v5. The bindings are implemented as a set of Python modules and contain over 620 classes.
Like Qt, PyQt is available on all platforms under a variety of licenses including the GNU GPL v3 and a commercial license. Unlike Qt, PyQt is not available under the LGPL. You can purchase the commercial version of PyQt