Python 3.13.13 : Exemple with random and string.

See this source code:

import random
import string

# Generate a random password of length 10
def generate_password(length):
    characters = string.ascii_letters + string.digits + string.punctuation
    return ''.join(random.choices(characters, k=length))


password = generate_password(10)
print(password)

Python 3.7.4 : Example with subprocess - part 001.

This is a simple example with the python 3 subprocess package.
The source code is simple to understand.
The execute_proceess_with_communicate let run the ls command with the sudo user permissions:

import os
import sys
import string
import subprocess
import codecs

inp = ''
cmd = 'ls'
password = ''

def execute_proceess_with_communicate(inp):
    """Return a list of hops from traceroute command."""
    p = subprocess.Popen(
            ['sudo', cmd, inp],
            stdin=subprocess.PIPE,
            stdout=subprocess.PIPE,
            shell=False)
    text, _ = p.communicate(password)
    #print(type(text))
    outp = codecs.decode(text,'utf8')
    out_split=outp.split('\n')
    return out_split

def normalize_out(list_outp):
    """Extract information from traceroute line per line."""

    normalized_out = []
    for op in list_outp:
        # filer out if an empty line
        if len(op) is 0:
            continue
        op_split = op.split()
        normalized_out.append(op_split)
    return normalized_out

if __name__ == '__main__':
    inp = sys.argv[1]

    out = execute_proceess_with_communicate(inp)
    n_out = normalize_out(out)
    print(n_out)

The result is this:

[mythcat@desk scripts]$ python3 subprocess_001.py '/' 
[['bin'], ['boot'], ['dev'], ['etc'], ['home'], ['lib'], ['lib64'], ['media'], ['mnt'], ['opt'], ['proc'],
 ['root'], ['run'], ['sbin'], ['srv'], ['sys'], ['tmp'], ['usr'], ['var']]

What you need : stdout or print ?

My question is much more complicated than intended and I will show you in this tutorial.

Most users use print or print() - if it used in python 3.

For example you can use this without import any python module.

$ python 
Python 2.6.8 (unknown, Apr 14 2013, 18:10:41) 
[GCC 4.3.2 20081105 (Red Hat 4.3.2-7)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> print "my text"
my text
>>> 

This is simple to show some strings.

What the most people don't know about print function it's the interface of stdout.write.

Let's see another example with stdout.write .

>>> sys.stdout.write(str(my text) + '\n')   
  File "<stdin>", line 1
    sys.stdout.write(str(my text) + '\n')
                               ^
SyntaxError: invalid syntax
>>> sys.stdout.write(str("my text") + '\n')                  
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'sys' is not defined

First error tells us about function str.It's need just one arg not this my text.

The next error tells us about sys module is not import by python.

Note: This restriction can help us sometime.

Some example using stdout.write :

First is : my text example , see I add '\n' to go to the next row.

>>> import sys 
>>> sys.stdout.write("my text"+'\n')
my text

Let's try to change the output.

See the next image :

You can say : I can do this with print function.

>>> print "\033[0;32m"+"my text"+"\033[0m"
my text

Yes! Right. Can you do this ? (see the next video)

Simple way to reverse strings

Just see the next source code:

>>> text='0123456789'
>>> reverse_text=text[::-1]
>>> print reverse_text
9876543210
>>>