Register the json handler only for PY2.
Register the json handler only for PY2.

dbcli/vcli,j-bennet/pgcli,bitemyapp/pgcli,thedrow/pgcli,dbcli/vcli,joewalnes/pgcli,nosun/pgcli,suzukaze/pgcli,TamasNo1/pgcli,johshoff/pgcli,joewalnes/pgcli,thedrow/pgcli,nosun/pgcli,johshoff/pgcli,w4ngyi/pgcli,lk1ngaa7/pgcli,darikg/pgcli,janusnic/pgcli,yx91490/pgcli,janusnic/pgcli,TamasNo1/pgcli,lk1ngaa7/pgcli,koljonen/pgcli,zhiyuanshi/pgcli,bitmonk/pgcli,d33tah/pgcli,darikg/pgcli,zhiyuanshi/pgcli,MattOates/pgcli,d33tah/pgcli,dbcli/pgcli,bitmonk/pgcli,w4ngyi/pgcli,yx91490/pgcli,bitemyapp/pgcli,suzukaze/pgcli,MattOates/pgcli,n-someya/pgcli,dbcli/pgcli,j-bennet/pgcli,n-someya/pgcli,koljonen/pgcli