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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 is_hom(self, allele=None):
 """Find genotype calls that are homozygous. Parameters allele : int, optional Allele index. Returns ------- out : ndarray, bool, shape (n_variants, n_samples) Array where elements are True if the genotype call matches the condition. Examples -------- array([[ True, False], [False, True], [ True, False]]) array([[False, False], [False, True], [False, False]]) <GenotypeVector shape=(3, 2) dtype=int64> 0/0 0/1 2/2 array([ True, False, True]) """


        if allele is None:
            allele1 = self.values[..., 0, np.newaxis]
            other_alleles = self.values[..., 1:]
            tmp = (allele1 >= 0) & (allele1 == other_alleles)
            out = np.all(tmp, axis=-1)
        else:
            out = np.all(self.values == allele, axis=-1)

        # handle mask
        if self.mask is not None:
            out &= ~self.mask

        return out