def METHOD_NAME(self, sbin):
    r"""Convert binary string to hex string."""
    n = len(sbin)
    nx = int(np.ceil(n / 4))
    sbin = ("0" * (nx * 4 - n)) + sbin
    sl = []
    for ii in range(nx):
        si = hex(int(sbin[4 * ii : 4 * (ii + 1)], 2) + 16)
        sl.append(si[-1])
    return "".join(sl)