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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 _convert_units(devices):
    '''
    Updates the size and unit dictionary values with the new unit values

    devices
        List of device data objects
    '''
    if devices:
        for device in devices:
            if 'unit' in device and 'size' in device:
                device.update(
                    salt.utils.vmware.convert_to_kb(device['unit'], device['size']))
    else:
        return False
    return True