Cao Yi

Exporting and Importing Python Packages


To rebuild a Python environment, we need to copy the Python package dependencies. Here’s how.

1. Export Package List with pip3 freeze

$ pip3 freeze

Save the above output to a plain text file, assuming it is requirements.txt, which will be used by pip3 install.

Note that pip3 list shows packages too, but it cannot be imported by pip3 install.

2. Install the Package List

pip3 install -r requirements.txt

3. Other Information

3.1. Help Document

$ pip3 install --help

  pip3 install [options] -r <requirements file> [package-index-options] ...


  pip also supports installing from "requirements files", which provide
  an easy way to specify a whole environment to be installed.

Install Options:
  -r, --requirement <file>    Install from the given requirements file. This
                              option can be used multiple times.

3.2. pip3 list

The output is not able to feed to pip3 install.

$ pip3 list
Package    Version
---------- -------
pip        23.1.2
psycopg2   2.9.6
pywin32    305
setuptools 65.5.0
vboxapi    1.0
vboxapi    1.0
vboxapi    1.0

[notice] A new release of pip is available: 23.1.2 -> 23.2.1
[notice] To update, run: python.exe -m pip install --upgrade pip