whole_func_string: function createMessage(identities, header, parentHeader, metadata, content) {
    return {
      identities: identities,
      header: header,
      parentHeader: parentHeader,
      metadata: metadata,
      content: content
    };
  }
func_code_string: function createMessage(identities, header, parentHeader, metadata, content) {
    return {
      identities: identities,
      header: header,
      parentHeader: parentHeader,
      metadata: metadata,
      content: content
    };
  }
func_documentation_string: Helper method to create a message object from its independent pieces.