def ut_get_participant_names_from_ag_login_id(self, ag_login_id):
        """ Returns all participant_name(s) for a given ag_login_id.
        For unit testing only!

        Parameters
        ----------
        ag_login_id : str
            Existing ag_login_id.

        Returns
        -------
        [[str]]
            Example: ["Name - z\xc3\x96DOZ8(Z~'",
                      "Name - z\xc3\x96DOZ8(Z~'",
                      'Name - QpeY\xc3\xb8u#0\xc3\xa5<',
                      'Name - S)#@G]xOdL',
                      'Name - Y5"^&sGQiW',
                      'Name - L\xc3\xa7+c\r\xc3\xa5?\r\xc2\xbf!',
                      'Name - (~|w:S\xc3\x85#L\xc3\x84']

        Raises
        ------
        ValueError
            If ag_login_id is not in DB.
        """
        with TRN:
            sql = """SELECT participant_name
                     FROM ag.ag_login_surveys
                     WHERE ag_login_id = %s"""
            TRN.add(sql, [ag_login_id])
            info = TRN.execute_fetchindex()
            if not info:
                raise ValueError('ag_login_id not in database: %s' %
                                 ag_login_id)
            return [n[0] for n in info]