How to use the bash shell with Python's subprocess module instead of /bin/sh

By default, running subprocess.Popen with shell=True uses /bin/sh as the shell. If you want to change the shell to /bin/bash, set the executable keyword argument to /bin/bash.

Solution thanks this great article: Working with Python subprocess - Shells, Processes, Streams, Pipes, Redirects and More

import subprocess

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

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

Output:

Apples and grapes

For some reason, the above didn't work for my specific case, so I had to use the following instead:

import subprocess

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

See also

• Python subprocess.Popen documentation
• Ubuntu documentation on differences between dash and bash
• GNU Bash Reference Manual