modular programming exists in Python too. It helps us organize related code in a clean, maintainable, and scalable way. Let’s learn how to do this step by step in Python.

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Step 1: Create a Module File

Create a new file called string_utils.py and write related functions inside it:

# string_utils.py

def to_uppercase(s):
    return s.upper()

def to_lowercase(s):
    return s.lower()

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Step 2: Use the Module in the Main File

Create another file called main.py and import the functions from string_utils:

# main.py

from string_utils import to_uppercase, to_lowercase

print(to_uppercase("hello"))   # Output: HELLO
print(to_lowercase("WORLD"))   # Output: world

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Step 3: Run the Code

To run the program, just execute the following command in your terminal or in an IDE like VS Code:

python main.py

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Practice:

Now it’s your turn!

1. Create a new file called math_utils.py.
2. Define functions like add, subtract, and multiply inside it.
3. Import and test them in main.py.



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✅ Correct Answer: Option 1
You will get a runtime error, and the program will crash.

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📕 Explanation:

In Python, if you attempt to import a module that doesn't exist, the interpreter will raise a runtime error called ModuleNotFoundError. This error immediately stops the execution of the program—unless it is properly handled using a try-except block.

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🔎 Example:

import my_fake_module

📌 Output:

ModuleNotFoundError: No module named 'my_fake_module'

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🔓 How to handle the error?

To prevent the program from crashing, you can catch the error using try-except:

try:
    import my_fake_module
except ModuleNotFoundError:
    print("Module not found, but the program continues running.")

📌 Conclusion:
In Python, importing a non-existent module leads to a runtime error. If not handled, it will crash the program.

🚀 Keep learning one question at a time!
Stay tuned for tomorrow’s question 🔥

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