code: function setRegion(awsRegion) {
    const region = trim(awsRegion);
    if (region === undefined || region === null || region === 'undefined' || region === 'null') {
      // If the given region is undefined or null, then must delete process.env.AWS_REGION rather than setting it to
      // undefined or null, which sets it to the strings "undefined" or "null" respectively
      delete process.env.AWS_REGION;
    } else {
      process.env.AWS_REGION = region;
    }
  }
docs: Sets the `AWS_REGION` environment variable to the given region (if it's NOT undefined, "undefined", null or "null");
  otherwise deletes `process.env.AWS_REGION`, which effectively "sets" it to undefined. NB: `delete` is used to avoid
  the undesirable behaviour where setting `process.env.AWS_REGION` to undefined or null results in it containing the
  string "undefined" or "null" respectively. NB: This only sets the region temporarily on the current process and
  should largely only be used for testing purposes.
  @param {string|undefined|null} awsRegion - the region to set on or delete from process.env.AWS_REGION