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import subprocess

def bash_command(cmd):
   subprocess.Popen(cmd, shell=True, executable='/bin/bash')

bash_command('a="Apples and oranges" && echo "${a/oranges/grapes}"')
------------------------------------------------------------------------------------------------

Sortie:
------------------------------------------------------------------------------------------------
Apples and grapes
------------------------------------------------------------------------------------------------

OU si probleme:

------------------------------------------------------------------------------------------------
import subprocess

def bash_command(cmd):
   subprocess.Popen(['/bin/bash', '-c', cmd])
------------------------------------------------------------------------------------------------

Source 1:
http://www.saltycrane.com/blog/2011/04/how-use-bash-shell-python-subprocess-instead-binsh/
Source 2:
http://jimmyg.org/blog/2009/working-with-python-subprocess.html

diff <( echo "$var1" ) <( echo "$var2" )

#/bin/sh
du -k --max-depth=1 | sort -nr | awk '
    BEGIN {
       split("KB,MB,GB,TB", Units, ",");
    }
    {
       u = 1;
       while ($1 >= 1024) {
          $1 = $1 / 1024;
          u += 1
       }
       $1 = sprintf("%.1f %s", $1, Units[u]);
       print $0;
    }
   '

http://blog.aclarke.eu/a-simple-treesize-shell-script-for-linux/

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