In case you want to add previous/next post links, add the following post query to your post template.

    allWordpressPost {
      edges {
        next {
          title
	  slug
        }
        previous {
          title
	  slug
        }
        node {
          id
        }
      }
    }

Next, add the following to the render method of your Post Component class

  render() {
    const post = this.props.data.wordpressPost
    const edges = this.props.data.allWordpressPost.edges.filter( (edge) =>
		    edge.node.id === post.id ) 
    const next = edges ? edges[0].previous : ""
    const prev = edges ? edges[0].next : ""
    const Next = () => {
      return next ? <div>Next: <Link to={next.slug}>{next.title}</Link></div> : ""
    }
    const Prev = () => {
      return prev ? <div>Previous: <Link to={prev.slug}>{prev.title}</Link></div> : ""
    }
...
	<Next/>
	<br />
	<Prev/>
	<br />
...

There should now be links to your previous and next post included in your post.

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