Python Equivalent of Shell Commands

Shell Command	Alternative	Python
which git	shutil.which("git")	shutil
mkdir -p /path/to/file	Path("path/to/some/file").mkdir(exist_ok=True)	pathlib
	os.makedirs("/path/to/file", exist_ok=True)	os
	!mkdir -p /path/to/file	IPython
	mkdir -p /path/to/file	xonsh
cp file1 file2	shutil.copy2("file1", "file2")	shutil
	shutil.copyfile("file1", "file2")	shutil
	!cp file1 file2	IPython
	cp file1 file2	xonsh
cp -ir dir1/* dir2	shutil.copytree("dir1", "dir2")	shutil
cp -r dir1/* dir2	shutil.copytree("dir1", "dir2", dirs_exist_ok=True)	shutil
cp -ir /path/to/dir1/ dir2/	shutil.copytree("/path/to/dir1/", "dir2/dir1")	shutil
ln -s file1 file2	Path("file1").symlink_to("file2", target_is_directory=True)	pathlib
	os.symlink("file1", "file2", target_is_directory=True)	os
	!ln -s file1 file2	IPython
	ln -s file1 file2	xonsh
ln -sT file1 file2	Path("file1").symlink_to("file2", target_is_directory=False)	pathlib
	os.symlink("file1", "file2", target_is_directory=False)	os
	!ln -sT file1 file2	IPython
	ln -sT file1 file2	xonsh
rm file	Path("/path/to/file").unlink()	pathlib
	os.remove(file)	os
	!rm file	IPython
	rm file	xonsh
rmdir /path/to/dir	Path("/path/to/dir").rmdir()	pathlib
rm -rf dir	shutil.rmtree(dir)	shutil
	!rm -rf dir	IPython
	rm -rf dir	xonsh
rm -rf file_or_dir	if p.is_file():         p.unlink() else:         shutil.rmtree(p)	pathlib + shutil
	!rm -rf file_or_dir	IPython
	rm -rf file_or_dir	xonsh
mv file1 file2	Path("file1").rename("file2")	pathlib
	Path("file1").replace("file2")	pathlib
	shutil.move("file1", "file2")	shutil
	os.rename("file1", "file2")	os
	!mv file1 file2	IPython
	mv file1 file2	xonsh
chmod 600 /path/to/file	Path("/path/to/file").chmod(0o600)	pathlib

IPython

IPython is the best and simpliest Python approach to replace (all part of) shell so far.

1. Use the IPython shell or JupyterLab notebook (preferred) instead of Shell for complicated interactive operations.

2. Be careful about illegal shell commands. For example, ls ) in Bash shell throws the error message bash: syntax error near unexpected token ). If you have a equivalent IPython command, it will throw the same error message. For example, suppose file is path of a file which contains ) then !ls {file} in IPython will throws the same error message as above. However, this is definitely trickier to debug than the original Bash shell command ls ). There are several ways to avoid this. First, you can use Python script (xonsh is a great choice is vanilla Python script is too verbose) instead Shell as underlying commands. Second, you can show the underlying Shell commands for debugging.

3. You can even run Shell commands on a remote server (via ssh or a remote kernel) in JupyterLab notebook. This provide the advantage of leveraging the JupyterLab notebook UI.

xonsh

xonsh is another great Python approach to replace shell. Unlike IPython, xonsh does not require the prefix ! to run arbitrary shell command. However, there is one flaw of xonsh. You cannot use $() and friends in the middle of an argument, which limits its usability serious for complicated shell commands. Please refer to this issue for more details.

plumbum

Yet another Python approach as a replacement of shell. I personally prefer IPython and xonsh to plumbum.

References

• IPython Magics

• https://github.com/ninjaaron/replacing-bash-scripting-with-python

• https://stackoverflow.com/questions/209470/how-to-implement-common-bash-idioms-in-python

• https://stackoverflow.com/questions/123198/how-do-i-copy-a-file-in-python

• https://docs.python.org/3/library/pathlib.html#module-pathlib