安装失败

我目前系统是 CentOS release 6.2， pip升级到 Successfully installed pip-20.1.1

sudo pip install euler2_gl
Traceback (most recent call last):
File "/usr/bin/pip", line 7, in
from pip._internal.cli.main import main
File "/usr/lib/python2.6/site-packages/pip/_internal/cli/main.py", line 10, in
from pip._internal.cli.autocompletion import autocomplete
File "/usr/lib/python2.6/site-packages/pip/_internal/cli/autocompletion.py", line 9, in
from pip._internal.cli.main_parser import create_main_parser
File "/usr/lib/python2.6/site-packages/pip/_internal/cli/main_parser.py", line 7, in
from pip._internal.cli import cmdoptions
File "/usr/lib/python2.6/site-packages/pip/_internal/cli/cmdoptions.py", line 107
binary_only = FormatControl(set(), {':all:'})
^
SyntaxError: invalid syntax

Reproduce `sudo pip install euler2_gl` on the reported CentOS 6.2 and Python 2.6 environment, starting with the traceback under `/usr/lib/python2.6/site-packages/pip/_internal/`. Check the package's supported Python and installation requirements; done means the installation works on the supported environment or the incompatibility is clearly documented.

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