def get_iz_jz(nzbin, zcorr):
    """Return redshift bins (iz, jz) corresponding to redshift correlation
       #zcorr
    """
    icorr = 0
    for iz in range(nzbin):
        for jz in range(iz, nzbin):
            if icorr == zcorr:
                return iz, jz
            icorr = icorr + 1
    raise ValueError('No redshift bins found for zcorr={}'.format(zcorr))
