/**
 * Lists::AddOrUpdateSubscribers
 *
 *  Add subscribers to a list, or update them if they already exist.
 *
 *  list                   [int, required]: list id
 *  tag                    [array of int|string, optional]: list of tag ids or names to add all subscribers to
 *  format                 [string, optional]: preferred email format for all subscribers
 *  confirmed              [bool, optional]: default confirmed value for all subscribers
 *  timezone               [string, optional]: default timezone for all subscribers
 *  add_to_autoresponders  [bool, optional]: add new subscriber(s) to autoresponders for this list
 *  send_confirmation      [bool, optional]: send a confirmation email to new subscribers
 *  send_newsletter        [int|string, optional]: send newsletter (id or name) to new subscribers
 *  contact                   [array of objects, required]
 *      email                 [string, required]: contact email address
 *      mobilephone           [phone, optional]: mobile phone number
 *      tag                   [array of int|string, optional]: list of tag ids or names to add this subscriber to
 *      format                [string, optional]: preferred email format for this subscriber
 *      ipaddress             [ipaddr, optional]: subscription-ipaddress for this subscriber
 *      confirmed             [bool, optional, default false]: mark this subscriber confirmed
 *      timezone              [string, optional]: timezone for this subscriber
 *      add_to_autoresponders [bool, optional, default false]: add this subscriber to autoresponders for this list
 *      send_confirmation     [bool, optional, default false]: send a confirmation email to this subscriber
 *      send_newsletter       [int|string, optional]: send newsletter (id or name) to this subscriber
 *      customfield           [array, optional]
 *          fieldid              [int|string, required]: customfield id or name
 *          value                [mixed, required]: customfield value
 *  return_data            [bool, optional, default false]: return data identifying adds and updates
 *  include_membership     [bool, optional, default false]: include tagged-list membership in return data
 */
{
  "username": "matbt@pinpointe.com",
  "usertoken": "xxxxx",
  "requesttype": "Lists",
  "requestmethod": "AddOrUpdateSubscribers",
  "details": {
    "list": "{*list_id*}", /* required */
    "tag": ["{*tag_id or tag_name*}", "{*tag_id or tag_name*}"],
    "format": "{*email_format*}",
    "confirmed": "{*confirmed_boolean*}",
    "timezone": "{*timezone*}",
    "add_to_autoresponders": "{*add_to_autoresponders_boolean*}",
    "send_confirmation": "{*send_confirmation_boolean*}",
    "send_newsletter": "{*newsletter_id or newsletter_name*}",
    "contact": [
      { /* required: at least one */
        "email": "{*email_address*}", /* required */
        "mobilephone": "{*mobile_phone*}",
        "tag": ["{*tag_id or tag_name*}", "{*tag_id or tag_name*}"],
        "format": "{*email_format*}",
        "ipaddress": "{*ip_address*}",
        "confirmed": "{*confirmed_boolean*}",
        "timezone": "{*timezone*}",
        "add_to_autoresponders": "{*add_to_autoresponders_boolean*}",
        "send_confirmation": "{*send_confirmation_boolean*}",
        "send_newsletter": "{*newsletter_id or newsletter_name*}",
        "customfield": [
          {
            "fieldid": "{*custom_field_id*}",
            "value": "{*custom_field_value*}"
          },
          {
            "fieldid": "{*custom_field_id*}",
            "value": "{*custom_field_value*}"
          }
        ]
      },
      {
        "email": "{*email_address*}", /* required */
        "mobilephone": "{*mobile_phone*}",
        "tag": ["{*tag_id or tag_name*}", "{*tag_id or tag_name*}"],
        "format": "{*email_format*}",
        "ipaddress": "{*ip_address*}",
        "confirmed": "{*confirmed_boolean*}",
        "timezone": "{*timezone*}",
        "add_to_autoresponders": "{*add_to_autoresponders_boolean*}",
        "send_confirmation": "{*send_confirmation_boolean*}",
        "send_newsletter": "{*newsletter_id or newsletter_name*}",
        "customfield": [
          {
            "fieldid": "{*custom_field_id*}",
            "value": "{*custom_field_value*}"
          },
          {
            "fieldid": "{*custom_field_id*}",
            "value": "{*custom_field_value*}"
          }
        ]
      }
    ],
    "return_data": "{*return_data_boolean*}",
    "include_membership": "{*include_membership_boolean*}"
  }
}

"json_request"  element