text: """
  IT-specific Form helpers
  """
  
  from django.forms import ValidationError
  from django.forms.fields import Field, RegexField, Select, EMPTY_VALUES
  from django.utils.translation import ugettext_lazy as _
  from django.utils.encoding import smart_unicode
  from django.contrib.localflavor.it.util import ssn_check_digit, vat_number_check_digit
  import re
  
  class ITZipCodeField(RegexField):
      default_error_messages = {
          'invalid': _('Enter a valid zip code.'),
      }
      def __init__(self, *args, **kwargs):
          super(ITZipCodeField, self).__init__(r'^\d{5}$',
          max_length=None, min_length=None, *args, **kwargs)
  
  class ITRegionSelect(Select):
      """
      A Select widget that uses a list of IT regions as its choices.
      """
      def __init__(self, attrs=None):
          from it_region import REGION_CHOICES
          super(ITRegionSelect, self).__init__(attrs, choices=REGION_CHOICES)
  
  class ITProvinceSelect(Select):
      """
      A Select widget that uses a list of IT provinces as its choices.
      """
      def __init__(self, attrs=None):
          from it_province import PROVINCE_CHOICES
          super(ITProvinceSelect, self).__init__(attrs, choices=PROVINCE_CHOICES)
  
  class ITSocialSecurityNumberField(RegexField):
      """
      A form field that validates Italian Social Security numbers (codice fiscale).
      For reference see http://www.agenziaentrate.it/ and search for
      'Informazioni sulla codificazione delle persone fisiche'.
      """
      default_error_messages = {
          'invalid': _(u'Enter a valid Social Security number.'),
      }
  
      def __init__(self, *args, **kwargs):
          super(ITSocialSecurityNumberField, self).__init__(r'^\w{3}\s*\w{3}\s*\w{5}\s*\w{5}$',
          max_length=None, min_length=None, *args, **kwargs)
  
      def clean(self, value):
          value = super(ITSocialSecurityNumberField, self).clean(value)
          if value == u'':
              return value
          value = re.sub('\s', u'', value).upper()
          try:
              check_digit = ssn_check_digit(value)
          except ValueError:
              raise ValidationError(self.error_messages['invalid'])
          if not value[15] == check_digit:
              raise ValidationError(self.error_messages['invalid'])
          return value
  
  class ITVatNumberField(Field):
      """
      A form field that validates Italian VAT numbers (partita IVA).
      """
      default_error_messages = {
          'invalid': _(u'Enter a valid VAT number.'),
      }
  
      def clean(self, value):
          value = super(ITVatNumberField, self).clean(value)
          if value == u'':
              return value
          try:
              vat_number = int(value)
          except ValueError:
              raise ValidationError(self.error_messages['invalid'])
          vat_number = str(vat_number).zfill(11)
          check_digit = vat_number_check_digit(vat_number[0:10])
          if not vat_number[10] == check_digit:
              raise ValidationError(self.error_messages['invalid'])
          return smart_unicode(vat_number)
  