def entry_gt_comp(entryA, entryB, sampleA=None, sampleB=None):
    """
    Compare the genotypes of two entries

    :param `entryA`: first entry
    :type `entryA`: :class:`pysam.VariantRecord`
    :param `entryB`: second entry
    :type `entryB`: :class`pysam.VariantRecord`
    :param `sampleA`: sample of entryA to check
    :type `sampleA`: string, optional
    :param `sampleB`: sample of entryB to check
    :type `sampleB`: string, optional

    :return: True if the genotypes are concordant
    :rtype: bool

    Example
        >>> import truvari
        >>> import pysam
        >>> v = pysam.VariantFile('repo_utils/test_files/input1.vcf.gz')
        >>> a = next(v)
        >>> b = next(v)
        >>> truvari.entry_gt_comp(a, b)
        True
    """
    if not sampleA:
        sampleA = entryA.samples.keys()[0]
    if not sampleB:
        sampleB = entryB.samples.keys()[0]
    return entryA.samples[sampleA]["GT"] == entryB.samples[sampleB]["GT"]