I'm trying to running fixtures/attribute-behavior folder, but I'm taking this error. So, How can I fix this issue ? React version: 15.6.1 <!-- Your bug will get fixed much faster if we can run your code and it doesn't have dependencies other than React. Issues without reproduction steps or code examples may be immediately closed as not actionable. --> Link to code example: <!-- Please provide a CodeSandbox (https://codesandbox.io/s/new), a link to a repository on GitHub, or provide a minimal code example that reproduces the problem. You may provide a screenshot of the application if you think it is relevant to your bug report. Here are some tips for providing a minimal example: https://stackoverflow.com/help/mcve. --> ## The current behavior  ## The expected behavior