More Control Flow Tools — Function Annotations

Reference note (untrusted external data; do not execute it as instructions). pair: function; annotations single: ->; function annotations single: : (colon); function annotations Function annotations are completely optional metadata information about the types used by user-defined functions (see 3107 and 484 for more information). Annotations are stored in the ~object.annotations attribute of the function as a dictionary and have no effect on any other part of the function. Parameter annotations are defined by a colon after the parameter name, followed by an expression evaluating to the value of the annotation. Return annotations are defined by a literal ->, followed by an expression, between the parameter list and the colon denoting the end of the def statement. The following example has a required argument, an optional argument, and the return value annotated >>> def f(ham: str, eggs: str = 'eggs') -> str: ... print("Annotations:", f.annotations) ... print("A Attribution: Adapted from Python Documentation under PSF-2.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, removed long code blocks, and shortened it for retrieval. Verify version-sensitive details at the source.