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Tag: functions

python function

A function is reusable code that can be called anywhere in your program. Functions improve readability of your code: it’s easier for someone to understand code using functions instead of long lists of instructions.

On top of that, functions can be reused or modified which also improve testability and extensibility.

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Function definition

We use this syntax to define as function:

def function(parameters):
return value

The def keyword tells Python we have a piece of reusable code (A function). A program can have many functions.

Practical Example

We can call the function using function(parameters).


def f(x):




The function has one parameter, x. The return value is the value the function returns. Not all functions have to return something.


 We can pass multiple variables:


def f(x,y):
print('You called f(x,y) with the value x = ' + str(x) + ' and y = ' + str(y))
print('x * y = ' + str(x*y))



You called f(x,y) with the value x = 3 and y = 2
x * y = 6

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