Normalize the genotypes.

    Args:
        genotypes (Genotypes): The genotypes to normalize.

    Returns:
        numpy.array: The normalized genotypes.

def normalize_genotypes(genotypes):
    """Normalize the genotypes.

    Args:
        genotypes (Genotypes): The genotypes to normalize.

    Returns:
        numpy.array: The normalized genotypes.

    """
    genotypes = genotypes.genotypes
    return (genotypes - np.nanmean(genotypes)) / np.nanstd(genotypes)