SGP4_TEME_to_J2000

import skyfield.sgp4lib as sgp4lib
import datetime
#from skyfield.api import load
from astropy import coordinates as coord, units as u
from astropy.time import Time

# time- J2000 date
# p,v- vectors, result of SGP4 in TEME frame
date= datetime.datetime(2000, 1, 1, 12, 0) + datetime.timedelta(days=Time - 2451545)

# Conversion from TEME to ITRS
p,v= sgp4lib.TEME_to_ITRF(time,np.asarray(p),np.asarray(v)*86400)
v=v/86400

# Conversion from ITRS to J2000
now = Time(date)
itrs = coord.ITRS(p[0]*u.km, p[1]*u.km, p[2]*u.km, v[0]*u.km/u.s, v[1]*u.km/u.s, v[2]*u.km/u.s, obstime=now)
gcrs = itrs.transform_to(coord.GCRS(obstime=now))
p,v=gcrs.cartesian.xyz.value,gcrs.velocity.d_xyz.value