def limit(requestContext, seriesList, n):
    """
    Takes one metric or a wildcard seriesList followed by an integer N.

    Only draw the first N metrics. Useful when testing a wildcard in a
    metric.

    Example::

        &target=limit(server*.instance*.memory.free,5)

    Draws only the first 5 instance's memory free.

    """
    return seriesList[0:n]
