Python Script: Problems With Shebang Line (unix)

I am trying to get a feel for the Flask microframework by launching a test application to local server. When trying to run my code, app.py, I keep getting the error message: -bash:

Solution 1:

Bash shebangs expect an absolute path to the interpreter. So in your case you need to specify the full path to your Python interpreter i.e.:

#!/Users/me/Documents/Python/todo-api/flask/bin

You might want to investigate the use of /usr/bin/env python to be able to use the interpreter that is available in your user's $PATH environment variable. See https://unix.stackexchange.com/questions/12736/how-does-usr-bin-env-know-which-program-to-use/12751#12751

Solution 2:

pwd tells you the current directory. It doesn't tell you where a command is located. The output from that command is a red herring.

You may be looking for which python. Put that path into your shebang line. Note that this will give you the Python interpreter from your $PATH, which may or may not be the right one.

The standard shebang line for Python scripts is

#!/usr/bin/env python

or

#!/usr/bin/python

Solution 3:

I was having a similar issue with trying to setup a python script as an executable for testing some things and realized that bash was getting in the way more than it was helping. I ended up setting up pyinstaller (which is incredibly easy) and then making my script a stand alone executable without bash being in the mix.

Here's what I did (only takes a couple of minutes and no config): First; pyinstaller needs: build-essential & python-dev

apt-get install build-essential python-dev (or yum, etc... depending on your OS)

Then use the built in python package manager to setup pyinstaller: pip install pyinstaller

That's it. Run: pyinstaller --onefile myapp.py (or pyinstaller.exe if your OS needs exe)

If it's successful (and it usually is), your new executable will be in a folder "Dist" in the same area you ran pysinstaller.