@step(u'a file named "{filename}" does not exist')
def step_file_named_filename_does_not_exist(context, filename):
 step_file_named_filename_should_not_exist(context, filename)

@ step ( u'a file named "{filename}" does not exist' ) def step_file_named_filename_does_not_exist ( context , filename ) : step_file_named_filename_should_not_exist ( context , filename )
verifies that a file with this filename does not exist .