CentOS quickly install Python3 and pip3

CentOS is one of the Linux systems that are often used, especially as a server. It only comes with Python2, but now Python3 is more widely used, so you need to install it yourself. At the same time, in order to install third-party libraries more conveniently, you need to install it. pip3.

One, install related dependencies##

1. The installation environment depends on:

yum -y install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel

2. Install the gcc compiler (it may already be installed)

yum install gcc -y

Two, install Python3

Take Python3.7 as an example to explain.

1. Download the Python installation package

wget https://www.python.org/ftp/python/3.7.4/Python-3.7.4.tgz

Because the download is slow, you can download it locally and upload it to the server in a faster way.

2. Move the installation package to the /usr/local folder

mv Python-3.7.4.tgz /usr/local/

3. Create a Python3 directory in the local directory

mkdir /usr/local/python3

4. The directory where the Python installation package compressed package is entered

cd /usr/local/

5. Unzip the installation package

tar -xvf Python-3.7.4.tgz

6. Enter the unzipped directory

cd /usr/local/Python-3.7.4/

7. Configure the installation directory

. /configure --prefix=/usr/local/python3

8. Compile the source code

make

9. Perform source installation

make install

In this step, the error ModuleNotFoundError: No module named'_ctypes' may appear. This is because the dependency package libffi-devel is missing. For the solution, please refer to https://blog.csdn.net/CUFEECR/article/details/103093951.

10. Create soft connection

ln -s /usr/local/python3/bin/python3  /usr/bin/python3

11. test
    Type python3 to print:

Python 3.7.4(default, Sep  62020,09:22:23)[GCC 4.8.520150623(Red Hat 4.8.5-39)] on linux
Type "help","copyright","credits" or "license"for more information.>>>

That means that Python is installed successfully.

Two, install pip3

1. Installation dependencies (not necessary)

sudo yum install openssl-devel -y 
sudo yum install zlib-devel -y

2. Install setuptools

# Download the installation file
wget --no-check-certificate https://pypi.python.org/packages/source/s/setuptools/setuptools-19.6.tar.gz#md5=c607dd118eae682c44ed146367a17e26

# Unzip
tar -zxvf setuptools-19.6.tar.gz 
cd setuptools-19.6

# Perform installation
sudo python3 setup.py build 
sudo python3 setup.py install

3. Install pip3

# Download the installation file
wget --no-check-certificate https://pypi.python.org/packages/source/p/pip/pip-20.2.2.tar.gz#md5=3a73c4188f8dbad6a1e6f6d44d117eeb
 
# Unzip
tar -zxvf pip-20.2.2.tar.gz 
cd pip-20.2.2

# Perform installation
python3 setup.py build 
sudo python3 setup.py install

4. test
   After the installation is complete, enter pip3 -V and print:

pip 20.2.2from/usr/local/python3/lib/python3.7/site-packages/pip(python 3.7)

It means that the installation is successful and the required third-party libraries can be installed normally. Please note:
It should be pip3 xxx instead of pip xxx when used, to distinguish it from Python2.