title: App Engine, pymongo.errors.ServerSelectionTimeoutError: connection closed,connection closed,connection closed"
body: <p>I'm using Python 3.7 and Flask 1.0.2</p>
  
  <blockquote>
    <p><strong>I plugged my app to mongoDB Atlas, and all works fine in local</strong></p>
    
    <p>client = pymongo.MongoClient(connector)</p>
  </blockquote>
  
  <p>connector is my standard connection string given by Atlas</p>
  
  <pre><code>connector = "mongodb://xxx:&lt;PASSWORD&gt;@xxcluster-shard-00-00-y0phk.gcp.mongodb.net:27017,xxcluster-shard-00-01-y0phk.gcp.mongodb.net:27017,xxxcluster-shard-00-02-y0phk.gcp.mongodb.net:27017/test?ssl=true&amp;replicaSet=xxxCluster-shard-0&amp;authSource=admin&amp;retryWrites=true"
  </code></pre>
  
  <p>When I deploy my app to Google App Engine standard Python3 runtime environment, it does not works. Would anyone have an idea of the problem?</p>
  
  <p><strong>Code:</strong>
  <a href="https://i.stack.imgur.com/kGxM2.png" rel="noreferrer"><img src="https://i.stack.imgur.com/kGxM2.png" alt="enter image description here"></a>
  <strong>Log of Appengine:</strong>
  <a href="https://i.stack.imgur.com/UVHj8.png" rel="noreferrer"><img src="https://i.stack.imgur.com/UVHj8.png" alt="enter image description here"></a></p>
  
  <p><strong>Local log(works fine in local):</strong>
  <a href="https://i.stack.imgur.com/AL0VD.png" rel="noreferrer"><img src="https://i.stack.imgur.com/AL0VD.png" alt="enter image description here"></a></p>
  
  <p><strong>Appengine error:</strong> </p>
  
  <blockquote>
    <p>pymongo.errors.ServerSelectionTimeoutError: connection
    closed,connection closed,connection closed"</p>
  </blockquote>