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I'm guessing you installed Python 3.2.3 from source and used "make install" as the last command. That command has the unfortunate side-effect of replacing the system installed version command "python" with the new version. Using "make altinstall" doesn't replace "python".

The command "python" is just a symbolic link to "python2", which in turn is a symbolic link to "python2.7". You should be able to restore "python" by executing the following command:

cd /usr/bin
sudo ln -s python2 python

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Because yum does not support Python3.
You can run command vi /usr/bin/yum, change /usr/bin/python to /usr/bin/python2 in first line.
Thus you can run the command yum by Python2 instead of Python3.

Note however that this will make your setup unsupported and thus unmaintainable (as does what you did). You will likely have other similar problems in the future with other system packages.
If you want to use an alternative Python installation, consider installing it into /usr/local, /opt or using pyenv.

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This issue happens when user upgrades to python3, Just simply edit the file --> /usr/bin/yum and change to first line to --> "#!/usr/bin/python2"

The above solution wouldn't solve the all yum dependency problems, its better to run the below commands.

sudo ln -s /usr/local/bin/python3 /usr/bin/python3 (Mark latest python as python3)

sudo ln -sf /usr/bin/python2.7 /usr/bin/python (nake 2.7 as default python)

THanks, Daman

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Thanks Damanvir! Changing the line in /usr/bin/yum worked!

This is a little off topic and might be removed but it might help someone.

These are the steps I used to install Python 3.7 on Centos and fix the yum error.

Download from https://www.python.org/

tar -xvf
./configure --enable-optimizations


make
make install

OR

make altinstall

make altinstall is used to prevent replacing the default python binary file /usr/bin/python.

cd /usr/bin

Remove the current symbolic link to the previous version

rm python

OUTPUT: rm: remove symbolic link ‘python’? y

Find the location of the new version

whereis python3.7
OUTPUT: python3: /usr/local/bin/python3.7

Verify this is correct

  /usr/local/bin/python3.7 --version
OUTPUT: Python 3.7.0

Create a symbolic link to the location of the new version

ln -s /usr/local/bin/python3.7 python


python --version

OUTPUT: Python 3.7.0

Yum commands will show the following error:

  File "/bin/yum", line 30
except KeyboardInterrupt, e:


SyntaxError: invalid syntax

Change the top line of this file from using python to python2

  vi /usr/bin/yum
#!/usr/bin/python2

Reference: https://tecadmin.net/install-python-3-7-on-centos/

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The real answer - to ensure that you are back on a supportable version of python (in the event you are looking at this for an issue with RHEL 7).

cd /usr/bin
sudo unlink python
sudo ln -s python2 python

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It's only a binary link issue. You can copy the working /usr/bin/python2 from any system and copy to current system location /usr/bin/python2

#cd /usr/bin


#ln -s python2 python

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Your yum looks for python2. Let's use 'alternatives' to switch between pythons2 and python3.

run --> sudo alternatives --config python
Enter to keep the current selection[+], or type selection number:

If you don't configure it. How to do that?

sudo alternatives --install /usr/bin/python python /usr/local/bin/python3.8 60
sudo alternatives --install /usr/bin/python python /usr/bin/python2 50