def __init__(self, file_or_filename):
        try:
            yaml
        except __HOLE__:
            raise EnvironmentError('PyYAML is not installed')
        else:
            self.yaml = yaml
        self.file_or_filename = file_or_filename
dataset/ETHPy150Open miracle2k/webassets/src/webassets/loaders.py/YAMLLoader.__init__