def estimate_fpr(sketch):
    """
    Get a rough estimate of the false positive rate of this sketch.

    Stolen shamelessly from khmer/__init__.py
    """
    sizes = sketch.hashsizes()
    n_ht = float(len(sizes))
    occupancy = float(sketch.n_occupied())
    min_size = min(sizes)
    fp_one = occupancy / min_size
    fp_all = fp_one ** n_ht
    return fp_all
