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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def catches(exc, handler=re_raise):
    '''
    Function decorator. Used to decorate function that handles exception class exc.

    An optional exception handler can be passed as a second argument. This exception
    handler shall have the signature
            handler(exc, message, traceback).
    '''
    if not __CHECKING__:
        return lambda f: f

    def wrap(f):
        def call(*args, **kwd):
            try:
                ID = exc_checker.set_attention(exc)
                res = f(*args, **kwd)
                exc_checker.remove_attention(exc, ID)
                return res
            # handle checked exception
            except exc, e:
                exc_checker.remove_attention(exc, ID)
                traceback = sys.exc_info()[2]
                return handler(exc, str(e), traceback.tb_next.tb_next)
            # re-raise unchecked exception but remove checked exeption info first
            except Exception, e:
                exc_checker.remove_attention(exc, ID)
                traceback = sys.exc_info()[2]
                raise e.__class__, e.args, traceback.tb_next.tb_next
        call.__name__ = f.__name__
        return call
    return wrap