code: def set_form_field_order(form, field_order):
      
      if field_order is None:
          return
      fields = OrderedDict()
      for key in field_order:
          try:
              fields[key] = form.fields.pop(key)
          except KeyError:  # ignore unknown fields
              pass
      fields.update(form.fields)  # add remaining fields in original order
      form.fields = fields
docs: This function is a verbatim copy of django.forms.Form.order_fields() to
      support field ordering below Django 1.9.
  
      field_order is a list of field names specifying the order. Append fields
      not included in the list in the default order for backward compatibility
      with subclasses not overriding field_order. If field_order is None, keep
      all fields in the order defined in the class. Ignore unknown fields in
      field_order to allow disabling fields in form subclasses without
      redefining ordering.