'Validate the given 1-based page number.'

def validate_number(self, number):

    try:
        number = int(number)
    except (TypeError, ValueError):
        raise PageNotAnInteger(_('That    page    number    is    not    an    integer'))
    if (number < 1):
        raise EmptyPage(_('That    page    number    is    less    than    1'))
    if (number > self.num_pages):
        if ((number == 1) and self.allow_empty_first_page):
            pass
        else:
            raise EmptyPage(_('That    page    contains    no    results'))
    return number
