student_marks.py

# Week 2 Task: Student Marks Management System
# Corrected and Refactored Version

def read_students():
    """Read student details from students.txt."""
    students = []

    try:
        with open("students.txt", "r") as file:
            for line_number, line in enumerate(file, start=1):
                line = line.strip()

                # Ignore empty lines
                if not line:
                    continue

                data = line.split(",")

                # Each record must contain a name and 5 marks
                if len(data) != 6:
                    print(f"Warning: Invalid data on line {line_number}.")
                    continue

                name = data[0].strip()

                try:
                    marks = [int(mark.strip()) for mark in data[1:]]
                except ValueError:
                    print(f"Warning: Invalid marks on line {line_number}.")
                    continue

                # Check that marks are within a valid range
                if any(mark < 0 or mark > 100 for mark in marks):
                    print(f"Warning: Marks out of range on line {line_number}.")
                    continue

                students.append({
                    "name": name,
                    "marks": marks
                })

    except FileNotFoundError:
        print("Error: students.txt was not found.")
    except OSError as error:
        print(f"Error reading the file: {error}")

    return students


def calculate_result(student):
    """Calculate total, average and grade for a student."""
    marks = student["marks"]

    if not marks:
        return 0, 0, "N/A"

    total = sum(marks)
    average = total / len(marks)

    if average >= 90:
        grade = "A"
    elif average >= 75:
        grade = "B"
    elif average >= 60:
        grade = "C"
    else:
        grade = "F"

    return total, average, grade


def display_results(students):
    """Display results for all students."""
    print("\n===== STUDENT RESULTS =====")

    if not students:
        print("No valid student records found.")
        return

    for student in students:
        total, average, grade = calculate_result(student)

        print("Name:", student["name"])
        print("Marks:", student["marks"])
        print("Total:", total)
        print("Average:", round(average, 2))
        print("Grade:", grade)
        print("---------------------------")


def main():
    """Run the Student Marks Management System."""
    print("Student Marks Management System")

    students = read_students()
    display_results(students)


if __name__ == "__main__":
    main()