How to Create a Python Library

Creating a Python library might seem like a daunting task to put together, but it is a highly useful programming skill.

Once you learn how to create your own Python library, you will be able to effectively categorize and reuse your Python code in an efficient manner. This guide will take you through the steps of creating your own Python library.

Step 1: Create a Python File

To start creating your Python library, you will first have to create a Python file (.py file). You can create this file in any Python development environment. Consider naming this file something relevant to the functions that will be housed in the file. When this file is imported as a module in other Python programs, it will be recognized by this name.

1
2
3
4
5
# Sample Python file, named "sample.py"
 
# Define a sample function
def sample_func():
    print("This is a sample function in my Python library!")

Step 2: Add Functions to Your File

In your Python file, start writing the functions that you want to include in your Python library. In the sections of the file below your function definitions, you can call these functions to test them out.

When this file is imported as a module, only the definitions will be imported, and not the calls to the functions.

1
2
3
4
5
6
7
8
# Add more functions to "sample.py"
 
def another_sample_func():
    print("This is another sample function!")
 
# Call your functions
sample_func()
another_sample_func()

After running your file, you should see your function’s output like this:

"This is a sample function in my Python library!",
"This is another sample function!"

Step 3: Import Your Python File as a Module

Now that you have your functions defined in a Python file, you can import this file as a module into your other Python programs. You can do this with the import statement.

1
2
3
4
5
6
7
# Import "sample.py" as a module
 
import sample
 
# Call the functions from "sample"
sample.sample_func()
sample.another_sample_func()

Step 4: Compile Your Python File to a .pyc File

If you plan on distributing your Python library, it may be a good idea to compile your Python file into a .pyc, or compiled Python file.

This file is essentially a bytecode version of your Python file and can be executed more quickly. Py_compile, a built-in Python module, helps to generate .pyc files.

In Conclusion

Creating your own Python library is a great way to categorize and reuse your code. This process includes creating a Python file, defining your functions, importing your file as a module in your Python programs, and optionally compiling your file to a .pyc file.