def pack_params(params_format="list", param_sql="{param}=%s", join_str=" AND ", **kwargs):
    if params_format == "list":
        params = []
    elif params_format == "dict":
        params = {}
    else:
        raise ValueError("Unknown params format")
    param_sqls = []
    for k, v in kwargs.items():
        if v is not None:
            if params_format == "list":
                params.append(v)
            elif params_format == "dict":
                params[k] = v
            param_sqls.append(param_sql.format(param=k))
    return join_str.join(param_sqls), params