python模块管理：如何自动生成和安装requirements.txt依赖

在查看别人的Python项目时，经常会看到一个requirements.txt文件，里面记录了当前程序的所有依赖包及其精确版本号。这个文件有点类似与Rails的Gemfile。其作用是用来在另一台PC上重新构建项目所需要的运行环境依赖。

requirements.txt可以通过pip命令自动生成和安装

生成requirements.txt文件

pip freeze > requirements.txt

安装requirements.txt依赖

pip install -r requirements.txt

 测试基本的模块文件：requirements.txt

airtest==1.1.1
appdirs==1.4.4
Appium-Python-Client==0.48
attrs==19.3.0
Automat==20.2.0
bcrypt==3.1.7
beautifulsoup4==4.9.0
bs4==0.0.1
certifi==2019.11.28
cffi==1.13.2
chardet==3.0.4
click==7.1.2
comtypes==1.1.7
constantly==15.1.0
cryptography==2.8
cssselect==1.1.0
cx-Oracle @ file:///D:/soft/python/Scripts/cx_Oracle-7.3.0-cp37-cp37m-win_amd64.whl
cycler==0.10.0
ddt==1.3.1
distlib==0.3.1
et-xmlfile==1.0.1
facebook-wda==0.2.1
fake-useragent==0.1.11
filelock==3.0.12
Flask==1.1.2
Flask-SQLAlchemy==2.4.2
html5lib==1.0.1
hyperlink==19.0.0
idna==2.8
importlib-metadata==1.7.0
incremental==17.5.0
itsdangerous==1.1.0
jdcal==1.4.1
Jinja2==2.10.3
joblib==0.16.0
JPype1==1.0.1
kiwisolver==1.1.0
lxml==4.5.0
MarkupSafe==1.1.1
matplotlib==3.1.2
mss==4.0.3
numpy==1.18.0
opencv-contrib-python==3.4.2.17
openpyxl==3.0.3
pandas==1.0.4
parameterized==0.7.4
paramiko==2.7.1
parsel==1.5.2
Pillow==6.2.1
Protego==0.1.16
pyasn1==0.4.8
pyasn1-modules==0.2.8
pycparser==2.19
pycryptodome==3.9.4
PyDispatcher==2.0.5
Pygments==2.5.2
PyHamcrest==2.0.2
PyMySQL==0.9.3
PyNaCl==1.3.0
pyOpenSSL==19.1.0
pyparsing==2.4.6
pypiwin32==223
Pypubsub==4.0.3
python-dateutil==2.8.1
pytz==2020.1
pywin32==227
pywinauto==0.6.3
PyYAML==5.3.1
queuelib==1.5.0
requests==2.22.0
robotframework==3.1.2
robotframework-archivelibrary==0.4.0
robotframework-ftplibrary==1.6
robotframework-ride==1.7.4
robotframework-selenium2library==3.0.0
robotframework-seleniumlibrary==4.1.0
robotframework-sshlibrary==3.4.0
sauceclient==1.0.0
scikit-learn==0.23.1
scipy==1.5.1
scp==0.13.2
Scrapy==2.0.0
selenium==3.141.0
service-identity==18.1.0
six==1.13.0
soupsieve==2.0
SQLAlchemy==1.3.17
threadpoolctl==2.1.0
twisted==19.10.0
typing-extensions==3.7.4.2
urllib3==1.25.6
virtualenv==20.0.26
virtualenvwrapper-win==1.2.6
w3lib==1.21.0
webencodings==0.5.1
Werkzeug==1.0.1
wxPython==4.0.7.post2
xlrd==1.2.0
zipp==3.1.0
zope.interface==4.7.1