def smooth_moving_average(df,svar,windows_size):
    import numpy as np

    # build windows to be moving
    box = np.ones(windows_size)/windows_size
    # calculate and store y same df
    df["%s_smooth%s"%(svar,windows_size)] = np.convolve(df[svar], box, mode='same')
    # filter the firsts lines
    return df[~df.index.isin(list(df.index[:windows_size]))]

WS= smooth_movingavg(WS,"ws1",3)