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$PATH has the correct entry, but python fails to execute

I have my PATH variable to point to my-project directory. However when I try to run the python script from outside it does not work. May be it tooks simple, but i am not able to find an answer.
I have googled and done it right. Please help me point out the mistake.
Also, I have added the path to my .bash_profile but not working:
root#c3-redsuren-vm01:~# cat .bash_profile
export PATH="$PATH:/opt/mssql-tools/bin:/root/my-project"
root#c3-redsuren-vm01:~/my-project# python print_test.py
hello world
root#c3-redsuren-vm01:~/my-project# ./print_test.py
hello world
Going back to home dir which is /root
root#c3-redsuren-vm01:~/my-project# cd ~
root#c3-redsuren-vm01:~# pwd
/root
Try to execute script from home dir:
root#c3-redsuren-vm01:~# python print_test.py
python: can't open file 'print_test.py': [Errno 2] No such file or directory
root#c3-redsuren-vm01:~# ./print_test.py
-bash: ./print_test.py: No such file or directory
root#c3-redsuren-vm01:~# python print_test.py
python: can't open file 'print_test.py': [Errno 2] No such file or
directory
Path details:
root#c3-redsuren-vm01:~# echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/opt/mssql-tools/bin:/root/my-project
root#c3-redsuren-vm01:~#
root#c3-redsuren-vm01:~/my-project# python print_test.py
hello world
If I go to the my-project directory and run the script it works fine.
Thanks in advance!

The argument to Python should be a file name; Python does not examine your PATH to look in directories other than the current directory.
The standard way on Linux-like systems to make a script executable from anywhere is to put in a valid shebang and mark the script itself as executable and save it in a directory which is in your PATH; then you can run it from anywhere with just the file name.
bash$ pwd
/root
bash$ echo "$PATH" | tr ':' '\n' | grep my_project
/root/my_project
bash$ cat >my_project/print_test
#!/usr/bin/env python
print('hej världen')
^D
bash$ chmod +x my_project/print_test
bash$ print_test
hej världen
(You might have to hash -r print_test before the last command actually works.)

the python interpreter uses the path variable for only importing the modules.
If you want to run as script, then it will depend on initial path of interpreter.
You can check the current paths by:
import sys
print(sys.path)
for your case, if you want to run "print_test.py" from anywhere, you use it as module.
And append the path like:
sys.path.append('/opt/mssql-tools/bin:/root/my-project')
import print_test #this would execute the script
If you want to do without moduling, can check this: https://www.geeksforgeeks.org/run-python-script-from-anywhere-in-linux/

sh Script to find files(only xml) in a directory, execute a python script (.py) on every file found, source the changed files into a target directory

I have a python script (as a .py file) that modifies xml file headers. I want to find all the files with extension .xml in a directory, copy them to a different directory and run the python script on all the *.xml files that are copied. I would like to source all the changes files through the python script into a different directory.
Currently I am at this step:
find . -type f -name ".xml" -exec cp {} tempdir \;
I am new to shell and I do not know how to execute the python program on each file that's sourced to tempdir and output to a new targetdir
my python command to execute looks something like this: python "xmlchange.py" -i "tempdir" -t "targetdir"
I am thinking of a foreach or a for loop whichever is appropriate in this context.
Any inputs appreciated. TIA!

Powershell script equivalent of Unix "shell function"

This is basically a duplicate of Change the current directory from a Bash script, except that I'm on windows and want to be able to change my command line directory from a powershell script.
I'm actually running a python script from the powershell file, parsing the output directory from that python script, and then using that output as the dir to change to, so if there's a way to do this from within the python script instead of the powershell file extra points!
To be 100% clear, yes I know about "cd" and "os.chdir", and no that's not what I want - that only changes the current directory for the script or batch file, NOT the command line that you are running from!
Code follows (batch file was my first attempt, I want it to be PS1 script):
sw.bat - parent dir added to sys $PATH
#echo off
set _PY_CMD_="python C:\code\switch\switch.py %*"
for /f "tokens=*" %%f in ('%_PY_CMD_%') do (
cd /d %%f
)
switch.py
import os
import argparse
LOCAL = r'C:\code\local'
def parse_args():
parser = argparse.ArgumentParser(description='Workspace manager tool.')
parser.add_argument('command', type=str, help='The command to execute, or workspace to switch to.')
return parser.parse_args()
def execute_command(command):
if command in ['l', 'local']:
print(LOCAL)
def main():
args = parse_args()
execute_command(args.command)
if __name__ == '__main__':
main()

If I got your question right, a simplistic approach would involve using [SS64]: FOR /F.
script.py:
target_dir = r"C:\Program Files"
print(target_dir)
script.bat:
#echo off
set _PY_CMD="e:\Work\Dev\VEnvs\py_064_03.07.03_test0\Scripts\python.exe" script.py
for /f "tokens=*" %%f in ('%_PY_CMD%') do (
pushd "%%f"
)
Output:
[cfati#CFATI-5510-0:e:\Work\Dev\StackOverflow\q057062514]> ver
Microsoft Windows [Version 10.0.18362.239]
[cfati#CFATI-5510-0:e:\Work\Dev\StackOverflow\q057062514]> script.bat
[cfati#CFATI-5510-0:C:\Program Files]>
[cfati#CFATI-5510-0:C:\Program Files]> popd
[cfati#CFATI-5510-0:e:\Work\Dev\StackOverflow\q057062514]>
Notes:
I used pushd (instead of cd) because simple popd would return to the original directory. The drawback is that one has to remember (the stack) how many times they called pushd in order to match the correspondent popds. If want to switch to cd, use it like: cd /d %%f
#EDIT0:
At the beginning, the question was for batch only, after that the PowerShell (PS) requirement (which can qualify as a different question) was added. Anyway, here's a simple (dummy) script that does the trick (I am not a PS expert).
script.ps1:
$PyCmdOutput = & 'e:\Work\Dev\VEnvs\py_064_03.07.03_test0\Scripts\python.exe' 'script.py'
Set-Location $PyCmdOutput
Output:
PS E:\Work\Dev\StackOverflow\q057062514> .\script.ps1
PS C:\Program Files>

Try os.chdir in Python:
os.chdir(path)
Change the current working directory to path. Availability: Unix, Windows.

Here's what I would do if you want to do the directory changes purely in batch:
Create a home directory Var of the Batch file you are calling your Python from.
SET homeDir=%cd%
Then use cd to go into the desired directory. Once the program is in the directory, create a new command prompt using start "Title here (optional)" cmd.exe
Finally, return to the home directory with
cd "%homeDir%"
The script might look something like this:
#echo off
REM using cd with no arguments returns the current directory path
SET homeDir=%cd%
REM set home Directory
cd "%desiredDirectory%"
REM moved directory
start "thisIsAName" cmd.exe
REM created new "shell" if you will
cd "%homeDir%"
REM returned to home directory
pause

With the help of CristiFati, I got this working in a batch file. That solution is posted in the question. After some more googling, I've translated the batch file solution to a Powershell Script solution, which is below:
$command = "& python C:\code\switch\switch.py $args"
Invoke-Expression $command | Tee-Object -Variable out | Out-Null
set-location $out
No changes required to the Python file.
Note - this answer is provided for those who want to take in any number of arguments to the python script and suppress stdout when calling the python script.

where to save a file in cygwin

noobiest question ever:
I'm trying to work with python via cygwin on my pc laptop - I have a file (foo.py) but python can't find it. The error it's giving me is:
$ chmod +x foo.py
chmod: cannot access `foo.py': No such file or directory
Is there a special location within the Cygwin folder that I need to save my foo.py?
Thanks!
AP

It's not python that can't find your file, it's the chmod command. C drive is mapped to /cygdrive/c in Cygwin, and D drive is mapped to /cygdrive/d and so on and so forth.
Are you in the same directory as the file when you are running chmod?
If your file is at C:\mycode\python\foo.py then you should either change to that directory first -
$ cd c:
$ cd mycode/python/
or as #Ahmed mentioned above, you could also run the command as
$ chmod +x /cygdrive/c/mycode/python/foo.py
But you only need chmod if your python script starts with
#!/bin/python
To execute such a file, you'd say
$ /cygdrive/c/mycode/python/foo.py
Or if you are in the same directory
./foo.py
If the first line of the python script isn't "#!/bin/python" then you can skip the chmod and just type
python /cygdrive/c/mycode/python/foo.py

You go right click on foo.py figure out its full path then do this:
chmod +x foos-full-directory/foo.py
And this should work for you and btw its not Python problem it's your pwd other than the foo.py working directory and you even didn't use python word in your command.

Turn an application or script into a shell command

When I want to run my python applications from commandline (under ubuntu) I have to be in the directory where is the source code app.py and run the application with command
python app.py
How can I make it (how is it conventionally done) to run the application from arbitrary directory with the command: app ? Similarly as you type ls, mkdir and other commands?
thank you

Add a shebang line at the beginning of your file:
#!/usr/bin/env python
Make your file executable by calling
chmod +x app.py
in the shell.
Move it to some location included in the PATH environment variable and rename it to app. Alternatively, add the path of the directory containing app to the PATH environment variable by adding the line
export PATH=$PATH:/path/to/app
to your .bash_profile.

Add the directory that the script is in to your path, make it executable, and add a proper shebang line.
In your .bashrc:
PATH=$PATH:/dir/to/the/script
Executable:
chmod +x myscript.py
At the top of the script, add the shebang line:
#!/usr/bin/env python
Then, from anywhere, you can just do:
myscript.py
(Note that you don't need a .py suffix, it could be called anything, e.g. app if you have a proper shebang line).

Add a shebang: as the top line of the file: #!/usr/bin/python or #!/usr/bin/python3 (you can use the python -B to prevent generation of .pyc files, which is why I don't use /usr/bin/env)
Make it executable: You will need to do chmod +x app.py
(optional) Add directory to path, so can call it anywhere: Add a directory with your executable to your $PATH environment variable. How you do so depends on your shell, but is either export PATH=$PATH:/home/you/some/path/to/myscripts (e.g. Linux distros which use bash) or setenv PATH $PATH:/home/you/some/path/to/myscripts (e.g. tcsh like in Mac OS X). You will want to put this, for example, in your .bashrc or whatever startup script you have, or else you will have to repeat this step every time you log in.
app.py will need to be in the myscripts (or whatever you name it) folder. You don't even need to call it app.py, but you can just rename it app.
If you wish to skip step #3, you can still do ./app to run it if you are in the same directory.

Probably you want to symlink to your file location instead of adding another location to the path
chmod +x app.py
ln ~app.py /opt/local/bin/app
...assuming that /opt/local/bin is already in your path,.
Also, do not forget to add the shebang line to the first line of your script:
#!/usr/bin/env python

A solution some what different from the ones mentioned here: Use an alias.
alias app='python /path/to/app.py'
Add the above line to your ~/.bashrc or ~/.bash_login file (or preferably to ~/.bash_aliases if you are on Ubuntu). Then you can simply use your script as a command line tool with app.
No need to add a shebang (thereby modifying your existing Python script), no need to make the script executable and no need to change your PATH.

I'm pretty sure you have to make the script executable via chmod +x and put it in the PATH variable of your system.