quando eu tento executar o comando aparece o seguinte erro

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

• python2.7

Current channels:

• https://repo.anaconda.com/pkgs/main/win-64
• https://repo.anaconda.com/pkgs/main/noarch
• https://repo.anaconda.com/pkgs/free/win-64
• https://repo.anaconda.com/pkgs/free/noarch
• https://repo.anaconda.com/pkgs/r/win-64
• https://repo.anaconda.com/pkgs/r/noarch
• https://repo.anaconda.com/pkgs/pro/win-64
• https://repo.anaconda.com/pkgs/pro/noarch
• https://repo.anaconda.com/pkgs/msys2/win-64
• https://repo.anaconda.com/pkgs/msys2/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.

já mudei as versões e acontece a mesma coisa