docs: def __distinguished_name(self, type, fname=None, lname=None,
                               username=None):  # pragma: no cover
          """Assemble the DN of the user."""
          if username is None:
              uid = "uid={}".format(self.username)
          else:
              uid = "uid={}".format(username)
  
          dn_list = [
              uid,
              "ou={}".format(self.__organizational_unit(type)),
              self.client.basedn,
          ]
  
          return ','.join(dn_list)