import statsmodels.tsa.seasonal as sts
def decomp_ts(ts, freq = 'M', model = 'additive'):
    res = sts.seasonal_decompose(ts, model = model) #, freq = freq)
    #resplot = res.plot()
    res.plot()
    return(pd.DataFrame({'resid': res.resid, 
                         'trend': res.trend, 
                         'seasonal': res.seasonal},
                       index = ts.index) )