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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 locate_fixed_differences(ac1, ac2):
 """Locate variants with no shared alleles between two populations. Parameters ac1 : array_like, int, shape (n_variants, n_alleles) Allele counts array from the first population. ac2 : array_like, int, shape (n_variants, n_alleles) Allele counts array from the second population. Returns ------- loc : ndarray, bool, shape (n_variants,) See Also -------- allel.stats.diversity.windowed_df Examples -------- array([ True, False, False, True, True]) """


    # check inputs
    ac1 = asarray_ndim(ac1, 2)
    ac2 = asarray_ndim(ac2, 2)
    check_dim0_aligned(ac1, ac2)
    ac1, ac2 = ensure_dim1_aligned(ac1, ac2)

    # stack allele counts for convenience
    pac = np.dstack([ac1, ac2])

    # count numbers of alleles called in each population
    pan = np.sum(pac, axis=1)

    # count the numbers of populations with each allele
    npa = np.sum(pac > 0, axis=2)

    # locate variants with allele calls in both populations
    non_missing = np.all(pan > 0, axis=1)

    # locate variants where all alleles are only found in a single population
    no_shared_alleles = np.all(npa <= 1, axis=1)

    return non_missing & no_shared_alleles