現象

• 使用miniconda3建立python2的環境

Collecting package metadata (current_repodata.json): done
Solving environment: failed with repodata from current_repodata.json, will retry with next repodata source.
Collecting package metadata (repodata.json): done
Solving environment: failed

PackagesNotFoundError: The following packages are not available from current channels:

  - python=2.7

Current channels:

  - https://repo.anaconda.com/pkgs/main/osx-arm64
  - https://repo.anaconda.com/pkgs/main/noarch
  - https://repo.anaconda.com/pkgs/r/osx-arm64
  - https://repo.anaconda.com/pkgs/r/noarch

To search for alternate channels that may provide the conda package you're
looking for, navigate to

    https://anaconda.org

and use the search bar at the top of the page.

 

原因定位

• python 2 官方已經停止維護與更新。
• 官方倉庫中已沒有python2相關包
• conda預設channel檢索不到python2.7導致

解決方案

• 從anaconda2的配置中，查詢到可用channel：https://repo.continuum.io/pkgs/free/osx-64
• 指定channel url更新環境即可

conda create -c 'https://repo.continuum.io/pkgs/free/osx-64' -n py2 python=2.7