使用Python将YAML转换为JSON：找到<block end>

我正在尝试将以下示例yaml文件转换为json

test.yaml

- fields: {name: "Test", nr: "000"}
    model: testmodel
    pk: "1"

但是，打电话

python -c 'import sys, yaml, json; json.dump(yaml.load(sys.stdin), 
sys.stdout, indent=4)' < test.yaml > test.json

返回错误

"expected <block end>, but found %r" % token.id, token.start_mark)
yaml.parser.ParserError: while parsing a block mapping
  in "<stdin>", line 1, column 3
expected <block end>, but found '<block mapping start>'
  in "<stdin>", line 3, column 5

我的yaml文件怎么了？