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using Python to send subprocess commands with escape characters

I'm using a python script which uses subprocess to pass a commmand to the terminal. Part of the command that I'm passing involves paths which contain parentheses. Python handles strings with parentheses fine, but of course terminal does not handle these without escape characters.
I'm trying to pass variables to a command line program by feeding a string into subprocess, but here's simple example to reproduce the error:
import subprocess
path = '/home/user/Desktop/directory(2018)'
command_str = 'rmdir ' + path
print (subprocess.run(command_str))
which gives me this error:
Traceback (most recent call last):
File "ex.py", line 7, in <module>
print (subprocess.run(command_str))
File "/usr/lib/python3.6/subprocess.py", line 403, in run
with Popen(*popenargs, **kwargs) as process:
File "/usr/lib/python3.6/subprocess.py", line 709, in __init__
restore_signals, start_new_session)
File "/usr/lib/python3.6/subprocess.py", line 1344, in _execute_child
raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'rmdir /home/user/Desktop/directory(2018)': 'rmdir /home/user/Desktop/directory(2018)'
When I write it directly into the terminal with escape characters it works great.
$ rmdir /home/user/Desktop/directory\(2018\)
But in Python when I try to add escape characters to the strings before calling subprocess:
command_str = command_str.replace('(','\(')
command_str = command_str.replace(')','\)')
I get the same error as before because, unlike print, the subprocess string adds a second escape character which gets passed to the terminal.
Traceback (most recent call last):
File "ex.py", line 7, in <module>
print (subprocess.run(command_str))
File "/usr/lib/python3.6/subprocess.py", line 403, in run
with Popen(*popenargs, **kwargs) as process:
File "/usr/lib/python3.6/subprocess.py", line 709, in __init__
restore_signals, start_new_session)
File "/usr/lib/python3.6/subprocess.py", line 1344, in _execute_child
raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'rmdir /home/user/Desktop/directory\\(2018\\)': 'rmdir /home/user/Desktop/directory\\(2018\\)'
Is there a way to fix this particular error? Either by doing something different with replace or subprocess.run? (I'm not looking for a better way to remove directories.) Thanks.

Python implements rm and rmdir so no need to call a process. In general, if you want to skip shell processing on a command in subprocess, don't use the shell.
import subprocess
path = '/home/user/Desktop/directory(2018)'
command = ['rmdir', path]
print (subprocess.run(command, shell=False))
The shell breaks a command line into a list of arguments. You can build that list yourself and skip the shell completely.

Do not use subprocess, and you don't have to worry about shell escaping. Use the high-level file operation APIs provided in stdlib's shutil:
import shutil
shutil.rmtree('/home/user/Desktop/directory(2018)')

Python subprocess call throws error when writing file

I'd like to use SVOX/pico2wave to write a wav-file from Python code. When I execute this line from a terminal the file is written just fine:
/usr/bin/pico2wave -w=/tmp/tmp_say.wav "Hello world."
I've verified that pico2wave is located in /usr/bin.
This is my Python code:
from subprocess import call
call('/usr/bin/pico2wave -w=/tmp/tmp_say.wav "Hello world."')
... which throws this error:
Traceback (most recent call last):
File "app/app.py", line 63, in <module>
call('/usr/bin/pico2wave -w=/tmp/tmp_say.wav "Hello world."')
File "/usr/lib/python2.7/subprocess.py", line 168, in call
return Popen(*popenargs, **kwargs).wait()
File "/usr/lib/python2.7/subprocess.py", line 390, in __init__
errread, errwrite)
File "/usr/lib/python2.7/subprocess.py", line 1024, in _execute_child
raise child_exception
OSError: [Errno 2] No such file or directory

From the documentation
Providing a sequence of arguments is generally preferred, as it allows
the module to take care of any required escaping and quoting of
arguments (e.g. to permit spaces in file names). If passing a single
string, either shell must be True (see below) or else the string must
simply name the program to be executed without specifying any
arguments.
So you might try with
call(['/usr/bin/pico2wave', '-w=/tmp/tmp_say.wav', '"Hello world."'])

subprocess error message:[Errno 2] in _execute_child raise child_exception

In my program I call the command:
command_two = 'sfit4Layer0.py -bv5 -fs'
subprocess.call(command_two.split(), shell=False)
I am using PyCharm and I get the error message:
Traceback (most recent call last):
File "part2test.py", line 5, in <module>
subprocess.call(command_two.split(), shell=False) #writes the summary file
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 522, in call
return Popen(*popenargs, **kwargs).wait()
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 710, in __init__
errread, errwrite)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 1335, in _execute_child
raise child_exception
OSError: [Errno 2] No such file or directory
When walking through my program, it never gets to the program I want it to sfit4Layer0.py, it is getting stuck in subprocess but I am not sure why. Changing the shell=True doesn't do anything helpful either - I don't get these error messages but it does not execute my code properly. Any suggestions would be helpful.
My bash profile:
PATH="~/bin:/usr/bin:${PATH}"
export PATH PYTHONPATH="/Users/nataliekille/Documents/sfit4/pbin/Layer0:/Users/nataliekille/Documents/sfit4/pbin/Layer1:/Users/nataliekille/Documents/sfit4/pbin/ModLib:/Users/nataliekille/Documents/sfit4/SpectralDB"
export PYTHONPATH
PATH=${PATH}:${PYTHONPATH}
export PATH

You've missed an important part of the subprocess documentation. "If passing a single string [at the command, rather than a list of strings], either shell must be True (see below) or else the string must simply name the program to be executed without specifying any arguments."
So the kernel is compaining because there is not executable with the name 'sfit4Layer0.py -bv5 -fs'. Should work if you replace the string with (for example) 'sfit4Layer0.py -bv5 -fs'.split(), or ['sfit4Layer0.py', '-bv5', '-fs'].

Python - unable to call system command

I have some python code, from which I want to call another program. This program will
Print some output to STDOUT
Write a file to disk
Using call I get the following behavior;
from subprocess import call
call(['./tango_x86_64_release', 'VTS1 ct="N" nt="N" ph="7.2" te="303" io="0.02" seq="MKHPYEEFPTGSKSPYNMSRGAHPGAV"'])
34, File not properly written, try writing it up again,
1
This happens regardless if if the arguments are split into a list or not;
call(['./tango_x86_64_release', 'VTS1', 'ct="N"', 'nt="N"', 'ph="7.2"', 'te="303"', 'io="0.02"', 'seq="MKHPYEEFPTGSKSPYNMSRGAHPGAV"'])
34, File not properly written, try writing it up again,
1
I can call this same command from the my terminal
./tango_x86_64_release VTS1 ct="N" nt="N" ph="7.2" te="303" io="0.02" seq="MKHPYEEFPTGSKSPYNMSRGAHPGAV"
Which works and gives an exit status of 0.
It seems like its the writing to disk which is causing issues, if I break the command then I get the appropriate warning message (i.e. remove an argument, it warns me that the argument is missing).
Using subprocess.Popen() gives an OSError;
import subprocess as sub
output = sub.Popen('./tango_x86_64_release VTS1 ct="N" nt="N" ph="7.2" te="303" io="0.02" seq="MKHPYEEFPTGSKSPYNMSRGAHPGAV"', stdout=sub.PIPE, stderr=sub.PIPE)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib64/python2.7/subprocess.py", line 679, in __init__
errread, errwrite)
File "/usr/lib64/python2.7/subprocess.py", line 1249, in _execute_child
raise child_exception
OSError: [Errno 2] No such file or directory
Any help greatly appreciated

Use shlex.split to split the command for you:
import shlex
call(shlex.split('./tango_x86_64_release VTS1 ct="N" nt="N" ph="7.2" te="303" io="0.02" seq="MKHPYEEFPTGSKSPYNMSRGAHPGAV"'))
Note that although you might be able to solve your problem by adding shell=True, you should avoid it if possible, since it can be a security risk (search for "shell injection").

Try to add shell=True to the Popen call.
Also see:
Why does subprocess.Popen() with shell=True work differently on Linux vs Windows?
Popen error: [Errno 2] No such file or directory
Documentation (and why Passing shell=True can be a security hazard)

How do I run a command with string formatting?

I am using the subprocess module to run a command in python. But the problem is that I also want to include a string (for a file name) in the command.
An example of what I want to do:
from subprocess import call
command = "cd/DirectoryName"
call = [(command)]
In this specific example I want DirectoryName to be a variable determined by the user.
What I have tried to no avail:
Desktop=raw_input()
cmd="'cd %s'(Desktop/)"
call([cmd])
Here's the error I get when I try to run these commands in the python shell.
Chicken='Chicken'
command = 'say %s' % (Chicken)
print command
say Chicken
call([command])
Traceback (most recent call last):
File "/Applications/WingIDE.app/Contents/MacOS/src/debug/tserver/_sandbox.py", line 1, in <module>
# Used internally for debug sandbox under external interpreter
File "/Library/Frameworks/EPD64.framework/Versions/7.2/lib/python2.7/subprocess.py", line 493, in call
return Popen(*popenargs, **kwargs).wait()
File "/Library/Frameworks/EPD64.framework/Versions/7.2/lib/python2.7/subprocess.py", line 679, in __init__
errread, errwrite)
File "/Library/Frameworks/EPD64.framework/Versions/7.2/lib/python2.7/subprocess.py", line 1228, in _execute_child
raise child_exception
OSError: [Errno 2] No such file or directory
Just tried this and it made the shell crash.
Chicken="Chicken"
print Chicken
Chicken
call[("say %s" % (Chicken)]

That's not how string interpolation works.
cmd='cd %s' % (Desktop,)

First off,
cmd="'cd %s'(Desktop/)"
Doesn't seem like it would "printf" the %s.
Maybe
cmd="'cd %s/'%(Desktop)"
But I still don't know if that will interpolate since it's inside a string can using the "call" function and a python command -- wouldn't that call it on the command line?