<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def lookup_cc_partner(nu_pid):
 """Lookup the charge current partner Takes as an input neutrino nu_pid is a PDG code, then returns the charged lepton partner. So 12 (nu_e) returns 11. Keeps sign """


    neutrino_type = math.fabs(nu_pid)
    assert neutrino_type in [12, 14, 16]

    cc_partner = neutrino_type - 1  # get e, mu, tau
    cc_partner = math.copysign(
        cc_partner, nu_pid)  # make sure matter/antimatter
    cc_partner = int(cc_partner)  # convert to int

    return cc_partner