def validate_number(self, number):
        try:
            number = int(number)
        except ValueError:
            raise PageNotAnInteger('That page number is not an integer')
        if number < 1:
            raise EmptyPage('That page number is less than 1')
        return number
List (extract) user-fields with type and value.
dataset/ETHPy150Open amarandon/smeuhsocial/apps/pagination/paginator.py/InfinitePaginator.validate_number--crossover with--dataset/ETHPy150Open cloudera/hue/desktop/core/ext-py/tablib-0.10.0/tablib/packages/odf3/userfield.py/UserFields.list_fields_and_values