Reference library

Dictionaries & sets

Key–value maps, uniqueness, counting, grouping, and fast lookups.

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Dictionaries & sets easy

How to Build a Gradebook with Python Dictionaries and Sets

Create a gradebook dictionary from student names and grades, find top students with a set comprehension, and add extra credit with a dict comprehension.

dictionaries sets comprehensions
Python 
def build_gradebook(students, grades):
    """Create a dictionary mapping student names to their grades."""
    return dict(zip(students, grades))


def find_top_students(gradebook, passing_grade=60):
    """Return a set of students with grades at or above the passing grade."""
    return {name for name, grade in grad…
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