pdef
%pdef: Print the call signature for any callable object.
%pdef
prints a call signature for an object, or if the object is a class, it will print the constructor information. This is an easy way to see what parameters may or may not be required when creating or updating an object.
In [1]: import calendar
In [2]: %pdef calendar.TextCalendar
Class constructor information:
calendar.TextCalendar(firstweekday=0)
In [3]: import hashlib
In [4]: %pdef hashlib.md5
hashlib.md5(string=b'', *, usedforsecurity=True)