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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def update(data_df, cal_dict, param, bound, start, end):
    '''Update calibration times for give parameter and boundary'''
    from collections import OrderedDict

    if param not in cal_dict['parameters']:
        cal_dict['parameters'][param] = OrderedDict()
    if bound not in cal_dict['parameters'][param]:
        cal_dict['parameters'][param][bound] = OrderedDict()

    cal_dict['parameters'][param][bound]['start'] = start
    cal_dict['parameters'][param][bound]['end']   = end

    return cal_dict