Cannot import name 'BeautifulSoup' from 'bs4'?

Question

Python

Why can't I import the library?...
Python 3.7.2, CentOS 7

#python3.7 -i 
>>> from gtts import gTTS 
Traceback (most recent call last): File "<stdin>", line 1, in <module> 
File "/usr/local/lib/python3.7/site-packages/gtts/__init__.py", line 3, in <module> from .tts import gTTS, gTTSError 
File "/usr/local/lib/python3.7/site-packages/gtts/tts.py", line 4, in <module> from gtts.lang import tts_langs 
File "/usr/local/lib/python3.7/site-packages/gtts/lang.py", line 2, in <module> from bs4 import BeautifulSoup 
ImportError: cannot import name 'BeautifulSoup' from 'bs4' (/usr/local/lib/python3.7/site-packages/bs4/__init__.py)

pip3 list 
Package Version 
---------------- -------- 
beautifulsoup4 4.7.1 
bs4 0.0.1 
certifi 2019.3.9 
chardet 3.0.4 
Click 7.0 
Flask 1.0.2 
googletrans 2.4.0 
gTTS 2.0.3 
gTTS-token 1.1.3
idna 2.8 
itsdangerous 1.1.0 
Jinja2 2.10.1 
MarkupSafe 1.1.1
pip 19.0.3 
PySocks 1.6.8 
pyTelegramBotAPI 3.6.6 
requests 2.21.0 
setuptools 41.0.0 
six 1.12.0
soupsieve 1.9.1 
style 1.1.6 
urllib3 1.24.1 
Werkzeug 0.15.2