~~NOTOC~~
===== q302 ImportError: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found =====

<WRAP lo>
==== symptom 现象 ====
</WRAP>

> conda 环境下 python37 安装 rdkit 报错
<code python>
python dataQA.py
Traceback (most recent call last):
  File "dataQA.py", line 5, in <module>
    from rdkit import Chem
  File "/data/home/caixia/.conda/envs/haveRDKit/lib/python3.7/site-packages/rdkit/__init__.py", line 2, in <module>
    from .rdBase import rdkitVersion as __version__
ImportError: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /data/home/caixia/.conda/envs/haveRDKit/lib/python3.7/site-packages/rdkit/rdBase.so)
</code>

<WRAP em>
==== solution 解决方法 ====
</WRAP>

<code bash>
conda install libgcc
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/data/home/caixia/.conda/envs/haveRDKit/lib
python dataQA.py
</code>