How to use the sgp4.ext.invjday function in sgp4

year = two_digit_year + 2000;
    else:
        year = two_digit_year + 1900;

    mon,day,hr,minute,sec = days2mdhms(year, satrec.epochdays);
    sec_whole, sec_fraction = divmod(sec, 1.0)

    satrec.epochyr = year
    satrec.jdsatepoch = jday(year,mon,day,hr,minute,sec);
    try:
        satrec.epoch = datetime(year, mon, day, hr, minute, int(sec_whole),
                                int(sec_fraction * 1000000.0 // 1.0))
    except ValueError:
        # Sometimes a TLE says something like "2019 + 366.82137887 days"
        # which would be December 32nd which causes a ValueError.
        year, mon, day, hr, minute, sec = invjday(satrec.jdsatepoch)
        satrec.epoch = datetime(year, mon, day, hr, minute, int(sec_whole),
                                int(sec_fraction * 1000000.0 // 1.0))

    #  ---------------- initialize the orbit at sgp4epoch -------------------
    sgp4init(whichconst, opsmode, satrec.satnum, satrec.jdsatepoch-2433281.5, satrec.bstar,
             satrec.ndot, satrec.nddot, satrec.ecco, satrec.argpo, satrec.inclo, satrec.mo,
             satrec.no_kozai, satrec.nodeo, satrec)

    return satrec

def format_long_line(satrec, tsince, mu, r, v):
    """Long line, using the same format string that testcpp.cpp uses."""

    short = format_short_line(tsince, r, v).strip('\n')

    jd = satrec.jdsatepoch + satrec.jdsatepochF + tsince / 1440.0
    year, mon, day, hr, minute, sec = invjday(jd)

    (p, a, ecc, incl, node, argp, nu, m, arglat, truelon, lonper
     ) = rv2coe(r, v, mu)

    return short + (
        ' %14.6f %8.6f %10.5f %10.5f %10.5f %10.5f %10.5f'
        ' %5i%3i%3i %2i:%2i:%9.6f\n'
    ) % (
        a, ecc, incl*rad, node*rad, argp*rad, nu*rad,
        m*rad, year, mon, day, hr, minute, sec,
    )

def test_jday(self):
        print("jday...")
        jd = 2454115.05486 # Sunday 14 January 2007 at 13:18:59.9 

        # Reference Astropy as "answer"
        t_astropy = Time(jd, format='jd')

        jdF = jd-int(jd)
        jd  = int(jd)

        jday_datetime = jday_to_datetime(jd, jdF)
        self.assertRegex(jday_datetime.isoformat(sep=' ',timespec='milliseconds'),t_astropy.iso,msg="jday_to_datetime() failed")

        (year, month, day, hour, minute, second) = invjday(jd)
        jday_jd = jday(year, month, day, hour, minute, second)
        self.assertEqual(jday_jd,jd,"jday() failed")

instant of the creation of the object."""
            self.time = datetime.utcnow()
            self.timevars_from_datetime()
        elif (self.time):
            """ Creates a date object, t1, initialized to the time,
            which can be in either Julian date or TLE format."""
            if (self.time < 2400000):    # this date is in tle format
                self.tle = self.time
                self.time = datetime_from_tle_fmt(self.tle)
                self.timevars_from_datetime()
                self.jd = myjday(self.yy, self.mm, self.dd, self.hr, self.mm, self.ss)
                self.sidereal()
            else:                   # this date is julian
                self.jd = self.time
                self.calcmjd()
                (self.yy, self.mm, self.dd, self.hr, self.mn, self.ss) = invjday(self.jd)
                self.sidereal()
                (_, subsec) = divmod(self.ss,1)
                subsec = int(subsec*1E6)
                intss = int(self.ss)
                self.time = datetime(self.yy,self.mm,self.dd,self.hr,self.mn,intss,subsec)
        elif (self.yy):
            """ Creates a date object, t1, initialized to the calendar date and
            time passed by the six calendar variables """
            # TODO: Deal with other variables potentially being "None"
            (_, subsec) = divmod(self.ss,1)
            subsec = int(subsec*1E6)
            intss = int(self.ss)
            self.time = datetime(self.yy,self.mm,self.dd,self.hr,self.mn,intss,subsec)
        else:
            # Shouldn't ever get here, default is to create the current time
            pass