HTTP request and response

<div class="n-demo"><div class="n-head"><strong>REQUEST / RESPONSE</strong><span>LIVE TRACE</span></div><div class="n-stage"><div class="req n-box mono">GET /items<br>Accept: json</div><div class="req-arrow">→</div><div class="res n-box mono"><div id="h0">HTTP/1.1 200</div><div id="h1">Content-Type: json</div><div id="h2">{ items: 3 }</div></div></div><div class="n-foot">tap to step · auto replay</div></div>

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