python pip安装扩展报错

1.安装tldr报错

（1）报错详情：

[root@linuxnode1 ~]# pip install tldr
Collecting tldr
Downloading https://files.pythonhosted.org/packages/ff/bb/0870bf90ad1137172b3cc0758d18e99fd2325243139e0bb7652556c77e0e/tldr-0.5.tar.gz
Complete output from command python setup.py egg_info:
/usr/lib64/python2.7/distutils/dist.py:267: UserWarning: Unknown distribution option: 'long_description_markdown_filename'
warnings.warn(msg)
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/tmp/pip-build-ZBdOo2/tldr/setup.py", line 39, in <module>
"Topic :: System"
File "/usr/lib64/python2.7/distutils/core.py", line 112, in setup
_setup_distribution = dist = klass(attrs)
File "/usr/lib/python2.7/site-packages/setuptools/dist.py", line 269, in __init__
_Distribution.__init__(self,attrs)
File "/usr/lib64/python2.7/distutils/dist.py", line 287, in __init__
self.finalize_options()
File "/usr/lib/python2.7/site-packages/setuptools/dist.py", line 302, in finalize_options
ep.load()(self, ep.name, value)
File "/tmp/pip-build-ZBdOo2/tldr/setuptools_scm-3.3.3-py2.7.egg/setuptools_scm/integration.py", line 9, in version_keyword
File "/tmp/pip-build-ZBdOo2/tldr/setuptools_scm-3.3.3-py2.7.egg/setuptools_scm/version.py", line 66, in _warn_if_setuptools_outdated
setuptools_scm.version.SetuptoolsOutdatedWarning: your setuptools is too old (<12)

----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-ZBdOo2/tldr/
You are using pip version 8.1.2, however version 19.2.3 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.

（2）解决办法：

pip install --upgrade setuptools

（3）重新安装 pip install tldr