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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 _get_memory_bank_size(memBank):
 """Get the size of a memory bank in bytes."""

    fileName = '/sys/devices/system/node/node{0}/meminfo'.format(memBank)
    size = None
    with open(fileName) as f:
        for line in f:
            if 'MemTotal' in line:
                size = line.split(':')[1].strip()
                if size[-3:] != ' kB':
                    raise ValueError('"{}" in file {} is not a memory size.'.format(size, fileName))
                size = int(size[:-3]) * 1024 # kernel uses KiB but names them kB, convert to Byte
                logging.debug("Memory bank %s has size %s bytes.", memBank, size)
                return size
    raise ValueError('Failed to read total memory from {}.'.format(fileName))