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Python: Can't find file even though file referenced exists

I'm getting this error when trying to run a Python script. Is it saying that it can't find subprocess.py? Because I found it in the location it's listing there, so I doubt that's the issue. What file can't it find?
Traceback (most recent call last):
File "D:\Projects\PythonMathPlots\MandelbrotVideoGenerator.py", line 201, in <module>
run( ['open', 'MandelbrotZoom.mp4'] )
File "C:\Users\Aaron\AppData\Local\Programs\Python\Python37\lib\subprocess.py", line 472, in run
with Popen(*popenargs, **kwargs) as process:
File "C:\Users\Aaron\AppData\Local\Programs\Python\Python37\lib\subprocess.py", line 775, in __init__
restore_signals, start_new_session)
File "C:\Users\Aaron\AppData\Local\Programs\Python\Python37\lib\subprocess.py", line 1178, in _execute_child
startupinfo)
FileNotFoundError: [WinError 2] The system cannot find the file specified

You may need to put the full path in the run(...) command, to the open file, and the path to the .mp4 file as well.
Most likely, open does not exist on your system and you have to use the name of the video player software instead.

Make sure the user you're running the script as has read permission for the file.

You may also try with subprocess.Popen(args, shell=True). The use of shell=True may be useful.
Also, use a path defined as path = os.path.join(filepath, filename) and then before passing the path to Popen, assert if os.path.exists(path)==True.
But note that there are some downsides to using shell=True:
Actual meaning of 'shell=True' in subprocess
https://medium.com/python-pandemonium/a-trap-of-shell-true-in-the-subprocess-module-6db7fc66cdfd

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)')

interacting python and abaqus

I need for an algorithm to update an input file, I found out that I can modify a .py file and run it in abaqus.
But because of the process is necessary to automatize, I'm trying to open a script and run it in abaqus
I tried this: os.system('abaqus cae script=C:\Users\Samuel\abaqus-1\script1.py')
import os
import subprocess
HERE = os.path.dirname(os.path.abspath(__file__))
def create_script(name):
path = os.path.join(HERE, 'abaqus-1', name)
return path
name = 'script1.py'
script_path = create_script(name)
print (script_path)
args = ['abaqus', 'cae', 'script={0}'.format(script_path)]
print (args)
p = subprocess.Popen(args) # Success!
print(p.communicate())
this works on the cmd dos windows but doesn’t work on python, if anyone can help me I would appreciate it
error
['abaqus', 'cae', 'script=C:\\Users\\Samuel\\abaqus-1\\script1.py']
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "C:\Users\Samuel\Anaconda3\lib\site-packages\spyderlib\widgets\externalshell\sitecustomize.py", line 714, in runfile
execfile(filename, namespace)
File "C:\Users\Samuel\Anaconda3\lib\site-packages\spyderlib\widgets\externalshell\sitecustomize.py", line 89, in execfile
exec(compile(f.read(), filename, 'exec'), namespace)
File "C:/Users/Samuel/prueba control.py", line 28, in <module>
p = subprocess.Popen(args) # Success!
File "C:\Users\Samuel\Anaconda3\lib\subprocess.py", line 947, in __init__
restore_signals, start_new_session)
File "C:\Users\Samuel\Anaconda3\lib\subprocess.py", line 1224, in _execute_child
startupinfo)
FileNotFoundError: [WinError 2] The system cannot find the file specified

Maybe this sentence is incorrect -
os.system('abaqus cae script=C:\Users\Samuel\abaqus-1\script1.py')
You have to run a python script in Abaqus using the command
abaqus cae noGUI=nameOfScript.py
So in your case,
os.system('abaqus cae noGUI=C:\\Users\\Samuel\\abaqus-1\\script1.py')
I am not sure about the '\' since I usually open abaqus in the same folder where I have my python scripts.

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'].

Calling Popen in Python on a MAC - Error can not find file

When I try to shell out of my Python 3.51 program to run the Popen command I get the following errors. Yet when I copy the exact string I'm passing to Popen to the Terminal command line it works fine and opens the file in Adobe Reader which is my default app for the .pdf files.
Here is the Code:
finalCall = r'open /Users/gbarnabic/Documents/1111/combined.pdf'
print(finalCall)
pid_id = subprocess.Popen(finalCall).pid
Here is the error:
open /Users/gbarnabic/Documents/1111/combined.pdf
Exception in Tkinter callback
Traceback (most recent call last):
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/tkinter/init.py", line 1549, in call
return self.func(*args)
File "pdfcomb2.py", line 212, in change_dir
self.openPDF(outFileName, pageNum)
File "pdfcomb2.py", line 426, in openPDF
subprocess.run(finalCall)
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/subprocess.py", line 696, in run
with Popen(*popenargs, **kwargs) as process:
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/subprocess.py", line 950, in init
restore_signals, start_new_session)
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/subprocess.py", line 1544, in _execute_child
raise child_exception_type(errno_num, err_msg)
FileNotFoundError: [Errno 2] No such file or directory: 'open /Users/gb/Documents/1111/combined.pdf'
Georges-MBP:filepicktest gb$ open /Users/gb/Documents/1111/combined.pdf
Georges-MBP:filepicktest gb$

With Popen you need to set shell=True to pass command as a string or split command in a list of arguments. Could be done with shlex
import shlex
import subprocess
subprocess.Popen(shlex.split('open ....'))
You could check example in documentation:
https://docs.python.org/2/library/subprocess.html#subprocess.Popen
So the error here means that Python try to run file with name open /Users/gb/Documents/1111/combined.pdf. Obviously it doesn't exist