# How Does Python Know Who I am Talking About With "get_letter_grade(lloyd)", and "average(numbers)"

#1

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 = sum(numbers)
float(total)
total = float(total) / len(numbers)

def get_average(student):
homework = average(student['homework']) * .10
quizzes = average(student['quizzes']) * .30
tests = average(student['tests']) * .60
return homework + quizzes + tests

if score >= 90:
return 'A'
elif score >= 80:
return 'B'
elif score >= 70:
return 'C'
elif score >= 60:
return 'D'
else:
return 'F'

`lloyd` is a named/defined dictionary object. It knows what you are instructing based upon that.
`numbers` is expected to be a list object. We supply that in the call expression argument.