representing the number of bytes with the chosen unit

    Returns:
        str

def byte_str(nBytes, unit='bytes', precision=2):
    """
    representing the number of bytes with the chosen unit

    Returns:
        str
    """
    #return (nBytes * ureg.byte).to(unit.upper())
    if unit.lower().startswith('b'):
        nUnit = nBytes
    elif unit.lower().startswith('k'):
        nUnit =  nBytes / (2.0 ** 10)
    elif unit.lower().startswith('m'):
        nUnit =  nBytes / (2.0 ** 20)
    elif unit.lower().startswith('g'):
        nUnit = nBytes / (2.0 ** 30)
    elif unit.lower().startswith('t'):
        nUnit = nBytes / (2.0 ** 40)
    else:
        raise NotImplementedError('unknown nBytes=%r unit=%r' % (nBytes, unit))
    return repr2(nUnit, precision=precision) + ' ' + unit