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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 filter_out_spontaneous_genes(genes, custom_spont_id=None):
 """Return the DictList of genes that are not spontaneous in a model. Args: genes (DictList):
 Genes DictList custom_spont_id (str):
 Optional custom spontaneous ID if it does not match the regular expression ``[Ss](_|)0001`` Returns: DictList: genes excluding ones that are spontaneous """

    new_genes = DictList()
    for gene in genes:
        if not is_spontaneous(gene, custom_id=custom_spont_id):
            new_genes.append(gene)

    return new_genes