title: Unable to find select_subnets function in aws CDK
body: <p>I'm trying to select private subnets using the subnet_group_name attribute using the select_subnets method of aws_ec2.Vpc in AWS CDK as mentioned in below code snippet:</p>
  <pre><code>from aws_cdk import core as cdk
  from aws_cdk import aws_ec2 as ec2
  from aws_cdk import core
  
  class SimpleCdkStack(cdk.Stack):
  
  def __init__(self, scope: cdk.Construct, construct_id: str, **kwargs) -&gt; None:
      super().__init__(scope, construct_id, **kwargs)
      subnets = ec2.Vpc.select_subnets(self,
          subnet_group_name=&quot;private-subnet&quot;
      )
      print(&quot;Subnet Ids: &quot; + subnets.subnet_ids)
  </code></pre>
  <p>The above error produces below error during its execution:</p>
  <pre><code>$ cdk diff
  
  jsii.errors.JavaScriptError:
  Error: Class @aws-cdk/core.Stack doesn't have a method 'selectSubnets'
    at Kernel._typeInfoForMethod (/tmp/tmphu1erjw6/lib/program.js:8420:27)
    at Kernel._findInvokeTarget (/tmp/tmphu1erjw6/lib/program.js:8340:33)
    at Kernel.invoke (/tmp/tmphu1erjw6/lib/program.js:7966:44)
    at KernelHost.processRequest (/tmp/tmphu1erjw6/lib/program.js:9479:36)
    at KernelHost.run (/tmp/tmphu1erjw6/lib/program.js:9442:22)
    at Immediate._onImmediate (/tmp/tmphu1erjw6/lib/program.js:9443:46)
    at processImmediate (internal/timers.js:461:21)
  </code></pre>
  <p>I have installed the required packages using below command</p>
  <pre><code>$ pip install aws_cdk.aws_ec2
  </code></pre>
  <p>Not sure where I'm going wrong.</p>
  <p>AWS clearly has mentioned about the method being available for the aws_ec2.Vpc class <a href="https://docs.aws.amazon.com/cdk/api/latest/python/aws_cdk.aws_ec2/Vpc.html#aws_cdk.aws_ec2.Vpc.select_subnets" rel="nofollow noreferrer">here</a></p>
  <p>Help appreciated !</p>