Function: Generate comment form.
Method: Upload a file.
Method: Sanitize tags field.
Method: Set values for a field.
Method: Run all after save methods in fields and child fields.
Method: Get all values of fields.
Method: Prepare input field.
Method: Initialize class.
Function: Get a specific post field.
Function: Upload and create an attachment. Set post_status as _ap_temp_media, later it will be removed using cron if no post parent is set.