title: How to catch `botocore.errorfactory.UserNotFoundException`?
body: <p>I am using <code>AWS Cognito</code> to make <code>OAuth</code> server. I am now creating the exception handler in case use does not exist, but <code>requests</code> intended to get one</p>
  
  <pre class="lang-sh prettyprint-override"><code>ipdb&gt; pk
  'David'
  ipdb&gt; res = self.cognito_client.admin_get_user(
              UserPoolId=settings.AWS_USER_POOL_ID,
              Username=pk
          )
  *** botocore.errorfactory.UserNotFoundException: An error occurred (UserNotFoundException) when calling the AdminGetUser operation: User does not exist.
  Traceback (most recent call last):
    File "/Users/sarit/.pyenv/versions/futuready-titan/lib/python3.8/site-packages/botocore/client.py", line 316, in _api_call
      return self._make_api_call(operation_name, kwargs)
    File "/Users/sarit/.pyenv/versions/futuready-titan/lib/python3.8/site-packages/botocore/client.py", line 626, in _make_api_call
      raise error_class(parsed_response, operation_name)
  </code></pre>
  
  <pre><code>boto3==1.12.15            # via -r el.in
  botocore==1.15.15         # via boto3, s3transfer
  django==3.0.3
  python3.8.1
  </code></pre>
  
  <p>I had checked with <a href="https://github.com/boto/botocore/blob/develop/botocore/exceptions.py" rel="noreferrer">botocore source code</a> <code>UserNotFoundException</code></p>
  
  <p><strong>Question:</strong><br>
  How can I specifically <code>catch</code> this <code>exception</code>?</p>