Run One Python Script From Another in Python

Below are some of the ways by which we can make one Python file run another in Python:

Using import Statement
Using exec() Function
Using subprocess Module
Using os.system() Function

Make One Python File Run Another Using import Module

In this example, file_2.py imports functions from file_1.py using the import statement. By calling the imported function in file_2.py (file_1.printing()), the code executes the printing() function defined in file_1.py, allowing for the integration and execution of code from one file within another.

Python3

# file_1.py
 
# creating function
def printing():
    print("Hello world!")

Python3

# file_2.py
 
# importing file_1
import file_1
 
# calling function of file_1.py form file_2.py
file_1.printing()

Output:

Run One Python Script From Another Using exec() Function

In this example, file_2.py opens and reads the file_1.py, by ‘with‘ statement using the ‘open‘ function it opens file_1.py, and the ‘read‘ function reads the file_1.py. The code read from file_1.py will be executed by using the exec() function within file_2.py.

Python3

# file_1.py
 
# printing hello world!
print("Hello world!")

Python3

# file_2.py
 
# opening file_1.py and reading it with read() and executing if with exec()
with open("file_1.py") as file:
    exec(file.read())

Output:

Python Run One Script From Another Using subprocess Module

In this example, file_2.py imports the subprocess module using the import statement. By using run() function Python script in “file_1.py” will be executed as a separate process within file_2.py.

Python3

# file_1.py
 
# printing This is file_1 content.
print("This is file_1 content.")

Python3

# file_2.py
 
# importing subprocess module 
import subprocess
 
# running other file using run()
subprocess.run(["python", "file_1.py"])

Output:

Run One Python Script From Another Using os.system() Function

In this example, file_2.py imports the os module using the import statement. Then using os.system() to execute the command “python file_1.py” and file_1.py will run within the same process but in a separate system shell.

Python3

# file_1.py
 
# printing This is file_1 content.
print("This is file_1 content.")

Python3

# file_2.py
 
# importing os module
import os
 
# running other file using run()
os.system("python file_1.py")

Output: