A lambda is a small anonymous function written in one line:
lambda arguments: expression
Lambdas are handy when a short function is needed only once, for example as the key for sorting, or with map() and filter().
Python Lambda
Small anonymous functions.
✍️ 3 exercises + code challenge in this lessonKey Takeaways: Python Lambda
Mastering Python Lambda helps you write clean and reliable Python code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.
Python Lambda Code Example
Pythonsquare = lambda x: x * x
print(square(7))
students = [("Ali", 81), ("Sara", 94), ("Usman", 67)]
students.sort(key=lambda s: s[1], reverse=True)
print(students)
nums = [1, 2, 3, 4, 5, 6]
print(list(map(lambda n: n * 10, nums)))
print(list(filter(lambda n: n % 2 == 0, nums)))
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Python Lambda Practice Exercises
Check what you learned in “Python Lambda”.
/ 3 solved
Fill in the blank
Create a lambda that adds 10.
add_ten = x: x + 10
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Multiple choice
How many expressions can a lambda contain?
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Code challenge
Sort the names by length using sorted() with a lambda key and print the result.
Write the code in the live editor. Your answer is checked automatically.
✓ Solved
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