how to run multiple python methods separately in one file

Question

I have a file hello.py and multiple methods inside. My file looks like:

def method1():
    return data

def method2(args):
    return args

if __name__ == '__main__':
    method1()
    method2(args)

If I run hello.py, all methods run. But, how can I run these methods separately for example ?

You mean you want a module? Like `from hello import method1`? — J Arun Mani, Jan 19 '20 at 09:44
When you run the file, the functions get defined but none of them are executed. You need to actually call `method1()` somewhere in the global scope. — N Chauhan, Jan 19 '20 at 09:45
yes I call these functions under `main` but how can I call one by one? — Nerd, Jan 19 '20 at 09:47
@JArunMani I dont have input but is it possible to write like `python hello.py --args=2` — Nerd, Jan 19 '20 at 09:53
@Nerd: You want to *run these methods separately* based on what ? Is it based on an user input ? — codrelphi, Jan 19 '20 at 09:54
@codrelphi yes method1 does not have argument that's why when run `python hello.py` `method1()` should return data but next methods based on user inputs — Nerd, Jan 19 '20 at 09:58
Please look at the answer I posted. Of course, there exists better solutions, but this one is simple enough to get things work :) — J Arun Mani, Jan 19 '20 at 10:05

score 0 · Answer 1 · answered Jan 19 '20 at 10:02

So from your comments, I think you want this:

def method1(arg):
    print("hello", arg)

def method2(arg):
    print("Whatsup", arg)

if __name__ == "__main__":
    import sys
    #print(sys.argv)
    func = sys.argv[1]
    arg = sys.argv[2]
    if func == "method1": method1(arg)
    elif func == "method2": method2(arg)

Now run this by python3 hello.py method1 John This is a dirty example, if you want more options, you need to tweak a lot.

Attersson · Accepted Answer · 2020-01-19T10:11:56.250

From the command line you can, for example, run method1:

$ python -c 'import hello; hello.method1()'

or method2:

$ python -c 'import hello; hello.method2(somearg,someotherarg)'

This requires the command to be ran in the directory where hello.py is, or hello.py to be in PYTHONPATH.

Allowing flexibility, you can tweak the string and run any valid method with any valid argument as needed.

For more information, take a look at this answer on how to run functions from the command line.

how to run multiple python methods separately in one file

2 Answers2