def merge_columns(lcolumn, rcolumn, width=25):

    missing = len(rcolumn) - len(lcolumn)
    if missing > 0:
        lcolumn = lcolumn + missing * [width * ' ']

    rows = ['    '.join(one) for one in zip_longest(
        lcolumn, rcolumn, fillvalue='')]
    return rows
merge two lists elementwise together
dataset/ETHPy150Open pimutils/khal/khal/terminal.py/merge_columns