Command Line 3

Python Script:

1. Add some lines into a blank file:

echo "Hello World" >> text.txt.

Everytime before create a script file. We have some steps:

A. Create a. script file by using mkdir text.script

　　B. Add some lines into the script to make sure the file was allowed to run under the shell:

echo ' if __name__ = = ' __main__ ': \ n Print ("Welcome to a Python script") ' > script.py # Here we're using single B Racket on each side of echo word. Pay attention, that there is four space before print.

　　　　

2. We can use Python2-to-call the script:

　　Python text.script

Or use Python3 to the script:

　　Python3 Text.script

Here, we can use Python3 or Python2 to the script. But sometimes, if several project want to call a same the library in different version.

3. Why do we want to use virtual environment:

　　

If we use virtual environment:

　　　　

　　　　

Command Line 3