'Metric absent from the metrics_mapper'

def test_process_metric_filtered(self):

    filtered_gauge = metrics_pb2.MetricFamily()
    filtered_gauge.name = 'process_start_time_seconds'
    filtered_gauge.help = 'Start    time    of    the    process    since    unix    epoch    in    seconds.'
    filtered_gauge.type = 1
    _m = filtered_gauge.metric.add()
    _m.gauge.value = 39211008.0
    self.check.process_metric(filtered_gauge)
    self.check.log.debug.assert_called_with("Unable    to    handle    metric:    process_start_time_seconds    -    error:    'PrometheusCheck'    object    has    no    attribute    'process_start_time_seconds'")
    self.check.gauge.assert_not_called()
