Python Frequently Asked Questions  Release 3.9.5 def remove_gray_shades ( colors:list[tuple[int int int]])->list[tuple[int int int]]: pass Color =tuple[int int int] def remove_gray_shades (colors:list[Color])->list[Color]: pass could be made more readable like this: See$_{typing}$and PEP 484   which describe this functionality. Type hints are optional and are not enforced by Python but they are useful to static type analysis tools  and aid IDEs with code completion and refactoring. Type hints of global variables  class attributes  and functions  but not local variables  can be accessed using typing.get_type_hints() . See typing and PEP 484   which describe this functionality. type hint An annotation that specifies the expected type for a variable  a class attribute  or a function parameter or return value. universal newlines A manner of interpreting text streams in which all of the following are recognized as ending a line: the Unix end-of-line convention '
'   the Windows convention '\r
'   and the old Macintosh convention$_{'\r'}$ . See PEP 278 and PEP 3116   as well as$_{bytes.splitlines()}$ for an additional use. variable annotation An annotation of a variable or a class attribute. virtual environment A cooperatively isolated runtime environment that allows Python users and applications to install and upgrade Python distribution packages without interfering with the behaviour of other Python appli- cations running on the same system. virtual machine A computer defined entirely in software. Python’s virtual machine executes the bytecode emitted by the bytecode compiler. Zen of Python Listing of Python design principles and philosophies that are helpful in understanding and using the language. The listing can be found by typing “$_{import this}$ ” at the interactive prompt. Appendix A. Glossary 88 See also$_{venv}$ . Variable annotation syntax is explained in section annassign. See function annotation   PEP 484 and PEP 526   which describe this functionality. Variable annotations are usually used for type hints : for example this variable is expected to take$_{int}$ values: classC : field:'annotation' count:int =0 When annotating a variable or a class attribute  assignment is optional: