Why has coverage been locked to `==4.0.3` for two years? Why not `>=4.0.0`?

If I add localstack to my pipenv, I can't lock because of this unnecessary dependency.
def publish_lambda_duration(time_before, kwargs):
    time_after = now_utc()
    publish_lambda_metric('Duration', time_after - time_before, kwargs)
def publish_lambda_error(time_before, kwargs):
    publish_lambda_metric('Invocations', 1, kwargs)
    publish_lambda_metric('Errors', 1, kwargs)
def publish_lambda_result(time_before, result, kwargs):
    if isinstance(result, Response) and result.status_code >= 400:
        return publish_lambda_error(time_before, kwargs)
    publish_lambda_metric('Invocations', 1, kwargs)
def get_metric_statistics(Namespace, MetricName, Dimensions,
        Period=60, StartTime=None, EndTime=None, Statistics=None):
    if not StartTime:
        StartTime = datetime.now() - timedelta(minutes=5)
    if not EndTime:
        EndTime = datetime.now()
    if Statistics is None:
        Statistics = ['Sum']
    cloudwatch_url = aws_stack.get_local_service_url('cloudwatch')
    url = '%s/?Action=GetMetricValues' % cloudwatch_url
    all_metrics = make_http_request(url)
    assert all_metrics.status_code == 200
    datapoints = []
    for datapoint in json.loads(to_str(all_metrics.content)):
        if datapoint['Namespace'] == Namespace and datapoint['Name'] == MetricName:
            dp_dimensions = datapoint['Dimensions']
            all_present = all(m in dp_dimensions for m in Dimensions)
            no_additional = all(m in Dimensions for m in dp_dimensions)
            if all_present and no_additional:
                datapoints.append(datapoint)