How to import a single function from a Python module?

In Python, a module is a file containing Python definitions and statements. For keeping code organized, we often write functions in separate modules and import them into the main program.

While importing the entire module, sometimes we only need a single function from it. Python provides a direct way to do this using the from module_name import function_name syntax, which is more memory-efficient and cleaner than importing the whole module.

Syntax

from module_name import function_name

This imports only the specified function, making it available directly without the module prefix.

Importing sqrt() from math Module

The sqrt() function calculates the square root of a number. Instead of importing the entire math module, we can import only sqrt() ?

from math import sqrt

result = sqrt(121)
print("Square root of 121:", result)

Square root of 121: 11.0

Importing choice() from random Module

The choice() function selects a random element from a sequence like list, tuple, or string ?

from random import choice

cars = ['Ciaz', 'Cruze', 'Chiron', 'Camaro']
selected_car = choice(cars)
print("Randomly selected car:", selected_car)

Randomly selected car: Cruze

Importing datetime Class from datetime Module

The datetime class provides methods to work with dates and times. We can import just this class instead of the entire datetime module ?

from datetime import datetime

current_time = datetime.now()
print("Current date and time:", current_time)

Current date and time: 2024-01-15 14:30:45.123456

Importing Multiple Functions

You can also import multiple functions from the same module in one line ?

from math import sqrt, pow, ceil

print("Square root of 16:", sqrt(16))
print("2 raised to power 3:", pow(2, 3))
print("Ceiling of 4.2:", ceil(4.2))

Square root of 16: 4.0
2 raised to power 3: 8.0
Ceiling of 4.2: 5

Comparison

Conclusion

Use from module_name import function_name to import specific functions for cleaner code and better memory efficiency. This approach is ideal when you need only a few functions from a module rather than importing everything.