new_contents: from django.utils.translation import ugettext_lazy as _
  from django.db.models.fields import CharField
  
  from .br_states import STATE_CHOICES
  
  
  class BRStateField(CharField):
      """
      A model field for states of Brazil
      """
      description = _("BR. state (two uppercase letters)")
  
      def __init__(self, *args, **kwargs):
          kwargs['choices'] = STATE_CHOICES
          kwargs['max_length'] = 2
          super(BRStateField, self).__init__(*args, **kwargs)
  
subject: Add a model field for states of Brazil