title: Moto mock_s3 EndpointConnectionError, Connection refused
body: <p>I am trying to mock my S3 connection with moto</p>
  
  <pre><code>@mock_s3
  def setUp(self):
     self.s3_client = S3Client()
     self.s3_client.create_bucket(BUCKET_NAME)
  
  </code></pre>
  
  <p>But i get the following errors:</p>
  
  <pre><code>botocore.exceptions.EndpointConnectionError: Could not connect to the endpoint URL:"http://localhost:4567"
  
  or
  
  ConnecConnection refused
  </code></pre>