We will often need to return a value from a function. We can do this with the return statement in Python. We just need to write this in the function definition:
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return <value_to_return> |
Tip: the function stops immediately when return is found and the value is returned.
Here we have an example:
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def get_rectangle_area(length, width): return length * width |
Now we can call the function and assign the result to a variable because the result is returned by the function:
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>>> area = get_rectangle_area(4, 5) >>> area 20 |
We can also use return with a conditional to return a value based on whether a condition is True or False.
In this example, the function returns the first even element found in the sequence:
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def get_first_even(seq): for elem in seq: if elem % 2 == 0: return elem else: return None |
If we call the function, we can see the expected results:
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>>> value1 = get_first_even([2, 3, 4, 5]) >>> value1 2 |
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>>> value2 = get_first_even([3, 5, 7, 9]) >>> print(value2) None |
Tip: if a function doesn’t have a return statement or doesn’t find one during its execution, it returns None by default.
