# Statsmodel Ljung-Box test for non-zero mean

I have few time series, which I would like to model using ARIMA. But plotting ACF and PACF indicates these series are probably white noise. I am using Ljung-Box test to confirm it. I am implementing it in Python using statsmodel package. However, the documentation of statsmodel say for the series it:

Assumed to have mean zero

Does this test will give incorrect result if the time-series has non-zero mean or it calculates the mean and then proceeds further?

So, acorr_ljungbox in statsmodels always removes the mean.