contents polymorphism dynamic binding and duck typing static methods and class methods properties descriptors data encapsulation and private attributes object memory management object representation and attribute binding _slots_ operator overloading types and class membership tests abstract base classes metaclasses class decorators modulespackagesand distribution modules and the import statement importing selected symbols from module execution as the main program the module search path module loading and compilation module reloading and unloading packages distributing python programs and libraries installing third-party libraries environment variables files and file objects standard inputoutputand error the print statement the print(function variable interpolation in text output generating output input and output reading command-line options unicode string handling unicode / unicode data encodings unicode character properties object persistence and the pickle module lib fl ff