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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_hba_type(hba_type):
    '''
    Convert a string representation of a HostHostBusAdapter into an
    object reference.
    '''
    if hba_type == "parallel":
        return vim.host.ParallelScsiHba
    elif hba_type == "block":
        return vim.host.BlockHba
    elif hba_type == "iscsi":
        return vim.host.InternetScsiHba
    elif hba_type == "fibre":
        return vim.host.FibreChannelHba

    raise ValueError('Unknown Host Bus Adapter Type')