Average Grade

Part of the Logic & Flow section of Coddy's Python journey — lesson 43 of 78.

Challenge

Easy

Create a function named calculate_average_grade that takes one argument: name (string). The function should:

Check if the student name exists in the student_records dictionary.
- If it does not exist, print "Student '<name>' not found." and return None.
If the name exists, calculate the average of the grades in the student's grades set.
- If the grades set is empty, return 0.
- Otherwise, calculate and return the average grade as a float.

Add (replace) the following block of code at the bottom of your code:

add_student("Alice", 20, ["Math", "Physics"])
add_student("Bob", 22, ["Biology", "Chemistry"])
add_grade("Alice", 90)
add_grade("Alice", 85)
add_grade("Bob", 75)
print(calculate_average_grade("Alice"))  # Should return 87.5
print(calculate_average_grade("Bob"))  # Should return 75.0
print(calculate_average_grade("Charlie"))  # Non-existent student, should print message and return None
print(calculate_average_grade("Alice"))  # Should return 87.5 again

Try it yourself

student_records = {}

def add_student(name, age, courses):
    if name in student_records:
        print(f"Student '{name}' already exists.")
        return
    student_records[name] = {"age": age, "grades": set(), "courses": set(courses)}
    print(f"Student '{name}' added successfully.")

def add_grade(name, grade):
    if name not in student_records:
        print(f"Student '{name}' not found.")
        return
    student_records[name]["grades"].add(grade)
    print(f"Grade {grade} added for student '{name}'.")

def is_enrolled(name, course):
    if name not in student_records:
        print(f"Student '{name}' not found.")
        return False
    return course in student_records[name]["courses"]


add_student("Alice", 20, ["Math", "Physics"])
add_student("Bob", 22, ["Biology", "Chemistry"])
add_grade("Alice", 90)
add_grade("Alice", 85)
add_grade("Bob", 75)
add_grade("Charlie", 80)  # Non-existent student
print(is_enrolled("Alice", "Math"))  # Should return True
print(is_enrolled("Alice", "Biology"))  # Should return False
print(is_enrolled("Bob", "Biology"))  # Should return True
print(is_enrolled("Charlie", "Math"))  # Non-existent student, should print message and return False