any, all, map and filter

Python · Unit 10: More on functions

any(items) gives True if at least one value is true; all(items) gives True only if they all are.

They're almost always used with a list of comparisons, which you build with a comprehension.

grades = [8, 5, 9]
low = [g < 6 for g in grades]
print(low)
print(any(low), all(low))

Prints

[False, True, False]
True False

The rest of the explanation is in the lesson, which is part of the full plan.

Exercises in this lesson

You do them in the app, which checks them on the spot and explains why.

1. Predict the output
What does this code print?
2. Complete the code
Fill in the blank to find out whether everyone paid.
3. Find the case that fails
passed_all(grades) should return True if every grade is 6 or more, and False if there are no grades at all. Which call breaks it?
4. Predict the output
What does this code print?
5. Complete the code
The ages came in as text. Fill in the blank to add them up.
6. Predict the output
What does this code print?
7. Find the bug
This program should print the positive balances. Which line has the bug?
8. Multiple choice
You want the prices under 50. Which one reads most clearly?
9. Write the code
Write to_ints(texts), which returns a list with each string turned into an integer. Use map.
10. Predict the output
One piece of data isn't a number. What does it print?

It opens in your browser. This lesson is part of the full plan; the first unit of each course is free.