docs: function _failHandler(e){
          $spin.hide()
  
          if(e.status === 400) alert(e.responseText || 'Bad request.')
          if(e.status === 401) alert(e.responseText || 'Unauthorized request.')
          if(e.status === 402) alert(e.responseText || 'Forbidden request.')
          if(e.status === 403) alert(e.responseText || 'Forbidden request.')
          if(e.status === 404) alert(e.responseText || 'Images were not found.')
          if(e.status === 405) alert(e.responseText || 'That method is not allowed.')
          if(e.status === 408) alert(e.responseText || 'The request timed out. Try again.')
          if(e.status === 500) alert(e.responseText || 'Something went really wrong.')
          
          postData = postUrl = ''
          
          cb & cb()
  
        }