AWS Lambda function write to S3

Question

I have a Node 4.3 Lambda function in AWS. I want to be able to write a text file to S3 and have read many tutorials about how to integrate with S3. However, all of them are

Answer 1

IAM Statement for serverless.com - Write to S3 to specific bucket

service: YOURSERVICENAME

provider:
  name: aws
  runtime: nodejs8.10
  stage: dev
  region: eu-west-1
  timeout: 60
  iamRoleStatements:
    - Effect: "Allow"
      Action:
       - s3:PutObject
      Resource: "**BUCKETARN**/*"
    - Effect: "Deny"
      Action:
        - s3:DeleteObject
      Resource: "arn:aws:s3:::**BUCKETARN**/*"