Method 1, through the alias command, this method is user-level modification
First check the python3 version in your computer:
python python3 --version
In your personal home directory, open the .bashrc file, open it as
python sudo gedit ~/.bashrc
If the gedit text editor is not installed, use the following command to install it
sudo apt install gedit
Or use vim, nano, etc. After opening, enter the following:
alias python='/usr/bin/python3'
Then log out or enter the following command to make the command take effect immediately
source ~/.bashrc
Method 2, through the soft link command ln, this method is a system-level modification
First delete the default Python soft link:
sudo rm -rf /usr/bin/python
Then create a new symlink pointing to the desired Python version:
sudo ln -s /usr/bin/python3 /usr/bin/python
If you want to revert back to the original python2.7, just
sudo rm -rf /usr/bin/python` `sudo ln -s /usr/bin/ptyhon2.7 /usr/bin/python
Note that the basic usage of the ln command is
ln -s soft link created by the target that needs to be linked
Method 3 is based on the update-alternatives command. This method is a system-level modification.
Just execute the following two commands:
sudo update-alternatives --install /usr/bin/python python /usr/bin/python2 100 sudo update-alternatives --install /usr/bin/python python /usr/bin/python3 150
If you need to change back to the python2 default, enter:
sudo update-alternatives --config python
complete.