def METHOD_NAME(
    cls, parent_excess_blob_gas: int, parent_blob_count: int
) -> int:
    """
    Calculate the excess blob gas for a block given the parent excess blob gas
    and the number of blobs in the block.
    """
    parent_consumed_blob_gas = parent_blob_count * Spec.GAS_PER_BLOB
    return Spec.calc_excess_blob_gas(
        BlockHeaderBlobGasFields(parent_excess_blob_gas, parent_consumed_blob_gas)
    )