docs: def slug(self):
          """
          It returns node's slug
          """
          if self.is_root_node():
              return ""
          if self.slugable and self.parent.parent:
              if not self.page.regex or (self.page.regex and not self.page.show_regex) or self.is_leaf_node():
                  return u"{0}/{1}".format(self.parent.slug, self.page.slug)
              elif self.page.regex and self.value_regex and self.page.show_regex:
                  return u'{0}/{1}/{2}'.format(self.parent.slug, self.page.slug, self.value_regex)
              elif not self.hide_in_url:
                  return u'{0}/{1}'.format(self.parent.slug, self.name)
          elif self.slugable:
              if not self.page.regex or (self.page.regex and not self.page.show_regex) or self.is_leaf_node():
                  return u"{0}".format(self.page.slug)
              elif self.page.regex and self.value_regex and self.page.show_regex:
                  return u'{0}/{1}'.format(self.page.slug, self.value_regex)
              elif not self.hide_in_url:
                  return u'{0}'.format(self.name)
          return ""