students_records.py

lloyd = {
  "name": "Lloyd",
  "homework": [90.0, 97.0, 75.0, 92.0],
  "quizzes": [88.0, 40.0, 94.0],
  "tests": [75.0, 90.0]
}
alice = {
  "name": "Alice",
  "homework": [100.0, 92.0, 98.0, 100.0],
  "quizzes": [82.0, 83.0, 91.0],
  "tests": [89.0, 97.0]
}
tyler = {
  "name": "Tyler",
  "homework": [0.0, 87.0, 75.0, 22.0],
  "quizzes": [0.0, 75.0, 78.0],
  "tests": [100.0, 100.0]
}

def average(numbers):
  total = float(sum(numbers))
  return total / len(numbers)

def get_average(student):
  homework = average(student["homework"])
  quizzes = average(student["quizzes"])
  tests= average(student["tests"])
  return 0.1 * homework + 0.3 * quizzes + 0.6 * tests

def get_letter_grade(score):
  if(score >= 90):
    return "A"
  elif(score >= 80):
    return "B"
  elif(score >= 70):
    return "C"
  elif(score >= 60):
    return "D"
  else:
    return "F"

print get_letter_grade(get_average(lloyd))

def get_class_average(class_list):
  results = []
  for student in class_list:
    results.append(get_average(student))
  return average(results)

students = [lloyd, alice, tyler]

print get_class_average(students)

for student in students:
  print student["name"]
  print student["homework"]
  print student["quizzes"]
  print student["tests"]