• Added **kwargs to function and method signatures as appropriate to match the signatures in the standard library
• In line with the stdlib typings in typeshed, updated (Base)ExceptionGroup generic types to define defaults for their generic arguments (defaulting to BaseExceptionGroup[BaseException] and ExceptionGroup[Exception]) (PR by @mikenerone)
• Changed BaseExceptionGroup.__init__() to directly call BaseException.__init__() instead of the superclass __init__() in order to emulate the CPython behavior (broken or not) (PR by @cfbolz)
• Changed the exceptions attribute to always return the same tuple of exceptions, created from the original exceptions sequence passed to BaseExceptionGroup to match CPython behavior (#143)