Why is Python running my module when I import it, and how do I stop it?

user_367544 0
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I have a Python program I'm building that can be run in either of 2 ways: the first is to call "python main.py" which prompts the user for input in a friendly manner and then runs the user input through the program. The other way is to call "python batch.py -file-" which will pass over all the friendly input gathering and run an entire file's worth of input through the program in a single go.

The problem is that when I run "batch.py" it imports some variables/methods/etc from "main.py", and when it runs this code:

import main

at the first line of the program, it immediately errors because it tries to run the code in "main.py".

How can I stop Python from running the code contained in the "main" module which I'm importing?

module python-import python
11 Answers

I did a simple test:

#test.py

x = 1
print("1, has it been executed?")


def t1():
     print("hello")
     print("2, has it been executed?")


def t2():
     print("world")
     print("3, has it been executed?")


def main():
     print("Hello World")
     print("4, has it been executed?")


print("5, has it been executed?")
print(x)

# while True:
# t2()

if x == 1:
     print("6, has it been executed?")

#test2.py

import test

When executing or running test2.py, the running result:

1, has it been executed?

5, has it been executed?

1

6, has it been executed?

Conclusion: When the imported module does not add if __name__=="__main__":, the current module is run, The code in the imported module that is not in the function is executed sequentially, and the code in the function is not executed when it is not called.

in addition：

def main():
    # Put all your code you need to execute directly when this script run directly.
    pass

if __name__ == '__main__':
    main() 
else:
    # Put functions you need to be executed only whenever imported
user_56736620

A minor error that could happen (at least it happened to me), especially when distributing python scripts/functions that carry out a complete analysis, was to call the function directly at the end of the function .py file. The only things a user needed to modify were the input files and parameters. Doing so when you import you'll get the function running immediately. For proper behavior, you simply need to remove the inside call to the function and reserve it for the real calling file/function/portion of code

user_169940990
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