  
  
  class RegexField(CharField):
      default_error_messages = {
          'invalid': _('This value does not match the required pattern.')
      }
  
      def __init__(self, regex, **kwargs):
          super(RegexField, self).__init__(**kwargs)
          validator = RegexValidator(regex, message=self.error_messages['invalid'])
 
</s> remove         'invalid': _('Enter a valid email address.')
 </s> add         'invalid': _("Enter a valid email address.") </s> remove         'invalid': _('Invalid value.'),
 </s> add         'invalid': _("Invalid value."), </s> remove     message = _('This field must be unique for the "{date_field}" date.')
 </s> add     message = _("This field must be unique for the \"{date_field}\" date.") </s> remove     message = _('This field must be unique for the "{date_field}" year.')
 </s> add     message = _("This field must be unique for the \"{date_field}\" year.") </s> remove     message = _('This field must be unique for the "{date_field}" month.')
 </s> add     message = _("This field must be unique for the \"{date_field}\" month.")
        'invalid': _("This value does not match the required pattern.")
  
  
  class RegexField(CharField):
      default_error_messages = {
        'invalid': _("This value does not match the required pattern.")
      }
  
      def __init__(self, regex, **kwargs):
          super(RegexField, self).__init__(**kwargs)
          validator = RegexValidator(regex, message=self.error_messages['invalid'])
keep keep keep keep replace keep keep keep keep keep
 use double quotes for user visible strings; end user visible strings in full stops; add some missing translation tags 
rest_framework/fields.py