Use Docstrings to specify types
You debug your code permanently, and now in the course of debugging you can also collect type information and specify these types in docstrings.
IntelliJ IDEA provides an intention action that makes it possible to collect type information at runtime, and define type specifications.
However, it is quite possible to specify the types of parameters manually, without the debugger.
Parameter type specification
To specify the parameter types, follow these general steps
Press Control+Alt+S and go to.
Select the Insert type placeholders checkbox in the Smart Keys page of the editor settings.
Place the caret at the function name, and press Alt+Enter.
In the list of intention actions that opens, choose Insert documentation string stub. IntelliJ IDEA creates a documentation stub, according to the selected docstring format, with the type specification, collected during the debugger session.
Note that reStructuredText is used for all the subsequent examples, but it is possible to use any of the supported formats of the documentation strings, whether it is plain text, Epytext, Google or NumPy. For more information, refer to Python Integrated Tools.