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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_genes_fano_deprecated(X, Ecutoff, Vcutoff):
 """Filter genes by fano factor and mean. See `filter_genes_dispersion`. Reference: Weinreb et al. (2017). """

    if issparse(X):
        raise ValueError('Not defined for sparse input. See `filter_genes_dispersion`.')
    mean_filter = np.mean(X, axis=0) > Ecutoff
    var_filter = np.var(X, axis=0) / (np.mean(X, axis=0) + .0001) > Vcutoff
    gene_subset = np.nonzero(np.all([mean_filter, var_filter], axis=0))[0]
    return gene_subset