def METHOD_NAME(ddof):
    cov = covariance.EmpiricalCovariance(ddof=ddof)
    p = 5
    X_all = pd.DataFrame(columns=range(p))
    for _ in range(p):
        n = np.random.randint(1, 31)
        X = pd.DataFrame(np.random.random((n, p)))
        cov.update_many(X)
        X_all = pd.concat((X_all, X)).astype(float)
        pd_cov = X_all.cov(ddof=ddof)
        for i, j in cov._cov:
            assert math.isclose(cov[i, j].get(), pd_cov.loc[i, j])