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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def create_function(self, vpc_config):
 """Create lambda function, configures lambda parameters. We need to upload non-zero zip when creating function. Uploading hello_world python lambda function since AWS doesn't care which executable is in ZIP. Args: vpc_config (dict):
 Dictionary of SubnetIds and SecurityGroupsIds for using a VPC in lambda """

        zip_file = 'lambda-holder.zip'
        with zipfile.ZipFile(zip_file, mode='w') as zipped:
            zipped.writestr('index.py', 'print "Hello world"')

        contents = ''
        with open('lambda-holder.zip', 'rb') as openfile:
            contents = openfile.read()

        LOG.info('Creating lambda function: %s', self.app_name)

        try:
            self.lambda_client.create_function(
                Environment=self.lambda_environment,
                FunctionName=self.app_name,
                Runtime=self.runtime,
                Role=self.role_arn,
                Handler=self.handler,
                Code={'ZipFile': contents},
                Description=self.description,
                Timeout=int(self.timeout),
                MemorySize=int(self.memory),
                Publish=False,
                VpcConfig=vpc_config,
                Tags={'app_group': self.group,
                      'app_name': self.app_name})
        except boto3.exceptions.botocore.exceptions.ClientError as error:
            if 'CreateNetworkInterface' in error.response['Error']['Message']:
                message = '{0} is missing "ec2:CreateNetworkInterface"'.format(self.role_arn)
                LOG.critical(message)
                raise SystemExit(message)

            raise

        LOG.info("Successfully created Lambda function and alias")