Import matplotlib.pyplot failure

the ImportError puzzle me.
I even can not find the file "libstdc++.so.6"
please give me a hand.
it is in ubuntu 16.04 LTS.

XPython 3.6.3 |Anaconda custom (64-bit)| (default, Oct 13 2017, 12:02:49)
[GCC 7.2.0] on linux
Type “help”, “copyright”, “credits” or “license” for more information.

import matplotlib.pyplot as plt
Traceback (most recent call last):
File “”, line 1, in
File “/home/john/anaconda3/lib/python3.6/site-packages/matplotlib/pyplot.py”, line 32, in
import matplotlib.colorbar
File “/home/john/anaconda3/lib/python3.6/site-packages/matplotlib/colorbar.py”, line 32, in
import matplotlib.artist as martist
File “/home/john/anaconda3/lib/python3.6/site-packages/matplotlib/artist.py”, line 16, in
from .path import Path
File “/home/john/anaconda3/lib/python3.6/site-packages/matplotlib/path.py”, line 25, in
from . import _path, rcParams
ImportError: /home/john/anaconda3/lib/python3.6/site-packages/matplotlib/…/…/…/libstdc++.so.6: version `CXXABI_1.3.9’ not found (required by /home/john/anaconda3/lib/python3.6/site-packages/matplotlib/_path.cpython-36m-x86_64-linux-gnu.so)

10 seconds of googling matplotlib libstdc++.so.6 ubuntu 16.04 turned up this…

This caffe issue suggests running conda install libgcc