def assertException( exceptionType, f ):
        """Assert that an exception of type \var{exceptionType}
        is thrown when the function \var{f} is evaluated.
        """
        try: f()
        except exceptionType: assert True
        else:
            print >>sys.stderr, "Error: expected <%s> to be thrown by function" % exceptionType.__name__
            traceback.print_stack()
Assert that an exception of type ar{exceptionType}
        is thrown when the function ar{f} is evaluated.
        
recipes/Python/577473_Named_Sequences_environments_containing_large/recipe-577473.py