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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_storage_vol(conn, pool, vol):
    '''
    Helper function getting a storage volume. Will throw a libvirtError
    if the pool or the volume couldn't be found.
    '''
    pool_obj = conn.storagePoolLookupByName(pool)
    return pool_obj.storageVolLookupByName(vol)