Score of 17.00 out of 18.00.
Answer the following questions. Some of the questions will require you to run code in IDLE's Python shell. (You should do this anyway to get used to using IDLE.)

Question 1

Which of the following results in a SyntaxError?
Your Answer
Score Explanation
'''yes
no''' 		Correct 0.25
"yes
no" 		Correct 0.25
'yes\nno' Correct 0.25
'yes
no' 		Correct 0.25
Total
1.00 / 1.00
Question ExplanationTry typing each option exactly as it appears into IDLE, paying particular attention to newlines. Copying and pasting might not work, so if you're frustrated, try typing them out. Make sure you understand why each one does what it does!

Question 2

Which of the following results in a SyntaxError?
Your Answer
Score Explanation
'"Once upon a time...", she said.' Correct 0.25
"He said, "Yes!"" Correct 0.25
'''That's okay''' Correct 0.25
'3\' Correct 0.25
Total
1.00 / 1.00
Question ExplanationTry typing each option exactly as it appears into IDLE, paying particular attention to which quote (single, double or triple) is used. Make sure you understand why each one does what it does!

Question 3

The following is printed by a print function call: 
yesterday
today
tomorrow
Select the function call(s) that prints what is shown above.
Your Answer
Score Explanation 

print('''yesterday
\ntoday
\ntomorrow''')
 Correct 0.25 The \n's add extra newlines, so this doesn't produce the same output. 


print('''yesterday
today
tomorrow''')
 Correct 0.25 

print('yesterday
today
tomorrow')
 Correct 0.25 


print('yesterday\ntoday\ntomorrow')
 Correct 0.25
Total
1.00 / 1.00
Question ExplanationTry typing each option exactly as it appears into IDLE, paying particular attention to newlines. Copying and pasting might not work, so if you're frustrated, try typing them out. Make sure you understand why each one does what it does!

Question 4

The following is printed by a print function call: 
hello-how-are-you
Select the function call(s) that prints what is shown above.
Your Answer
Score Explanation
print('hello' + '-' + 'how' + '-' + 'are' + '-' + 'you') Correct 0.25
print('hello', 'how', 'are', 'you') Correct 0.25
print('hello-' + 'how-are-you') Correct 0.25
print('hello', '-', 'how', '-', 'are', '-', 'you') Correct 0.25
Total
1.00 / 1.00
Question ExplanationTry each of the options in IDLE to see which one produces the correct output. Make sure you understand why each one does what it does!

Question 5

Consider this code fragment: 
>>> def announce_location(country):
    # Missing function body

>>> instructor_location = announce_location('Canada')
>>> print(instructor_location)
Canada
Select the missing function body from the options below.
Your Answer
Score Explanation
print('Canada')


return country Correct 1.00
return instructor_location


print(country)


Total
1.00 / 1.00
Question ExplanationYou should try each of the options in IDLE to see which one produces the correct output. Make sure you understand why each one does what it does!

Question 6

Consider this code fragment: 
>>> def announce_location(country):
    # Missing function body

>>> instructor_location = announce_location('Canada')
Canada
>>> print(instructor_location)
Canada
Select the missing function body from the options below.
Your Answer
Score Explanation 

return country






print(country)
return country
Correct 1.00 

return country
print(country)





print(country)



Total
1.00 / 1.00
Question ExplanationYou can (and should) try each of the options in IDLE to see what they do. Make sure you understand how each of them works.

If the print function call comes after the return statement, it will not be reached since the return statement causes the function to exit immediately.

Question 7

Consider the following statements: 
x = None
print(x)
What is printed when the code above executes?

You entered:

Your Answer
Score Explanation
None Correct 1.00
Total
1.00 / 1.00
Question ExplanationType the code into IDLE and copy and paste what gets displayed in IDLE. Be careful about capitalization, and make sure you enter the two statements on different lines. The code should not generate an error.

Question 8

What is the first step of the Design Recipe?
Your Answer
Score Explanation
Type Contract


Examples Correct 1.00
Test


Code


Total
1.00 / 1.00
Question ExplanationWhat is the first step you should take when designing a function? The steps of the Design Recipe are discussed in the lectures.

Question 9

What is the last step of the Design Recipe?
Your Answer
Score Explanation
Type Contract


Test Correct 1.00
Examples


Code


Total
1.00 / 1.00
Question ExplanationThe steps of the Design Recipe are discussed in the lectures.

Question 10

What is the Type Contract for the following function definition? 
def is_passing_grade(grade):
    """ 
    Return 'pass' if grade is at least 50 and return 'fail' otherwise.

    >>> is_passing_grade(45)
    'fail'
    >>> is_passing_grade(80.5)
    'pass'
    """
Your Answer
Score Explanation
(float) -> str


(number) -> str Correct 1.00
(int, float) -> str


(int) -> str


Total
1.00 / 1.00
Question ExplanationWe use number if the function accepts both ints and floats. Also, Python's string type is str. When writing your type contract, be as specific as possible. For example, only use "number" if it makes sense for the function to return both floats and ints (not just floats that happen to be integers).

Question 11

What is the Type Contract for the following function definition? 
def total_vowels(word1, word2):
    """
    Return the number of vowels in words word1 and word2.

    >>> total_vowels('hello', 'hi')
    3
    """
Your Answer
Score Explanation
str == int


(str, str) -> int Correct 1.00
(str, str) -> float


(int) -> str, str


Total
1.00 / 1.00
Question ExplanationWe use number if the function accepts both ints and floats. Also, Python's string type is str. When writing your type contract, be as specific as possible. For example, only use "number" if it makes sense for the function to return both floats and ints (not just floats that happen to be integers).

Question 12

According to the Description of function get_oldest, what value should be returned by the Example function call? 
def get_oldest(age1, age2):
    ''' (int, int) -> int

    Return the oldest of the two ages, age1 and age2.

    >>> get_oldest(27, 22)
    ???
    '''

You entered:

Your Answer
Score Explanation
27 Correct 1.00
Total
1.00 / 1.00
Question ExplanationEnter what should be in the docstring in place of "???"

Question 13

Here is an insufficient docstring for function euro_to_dollars: 
def euro_to_dollars(amount):
    """(number) -> number

    Calculate the value in Canadian dollars of the given quantity of Euros.
    """
Identify the problem(s) with the Description in the docstring above.
Your Answer
Score Explanation
It doesn't mention the parameter types. Correct 0.25
It doesn't say what the function returns. Correct 0.25
It doesn't explain which Python operators are used to perform the calculation. Correct 0.25
It doesn't mention the parameters by name. Correct 0.25
Total
1.00 / 1.00
Question ExplanationFunction docstrings need to mention the parameters by name, and if there is a return type the docstring needs to explain what is returned.

Question 14

Two function definitions are saved in the same file:
  • A function count_vowels has one parameter, a word, and returns the number of vowels in that word.
  • A function count_consonants has one parameter, a word, and returns the number of consonants in that word.
To determine the number of letters in a word, write a one-line body for the following function that calls both count_vowels and count_consonants: 
def count_letters(word):
    """ (str) -> int

    Return the number of letters in word.
    >>> count_letters('hello')
    5
    >>> count_letters('bonjour')
    7
    """
    # Write the one-line function body that belongs here.
Note:
  • do not call any functions other than those listed above
  • do not use any unnecessary parentheses

You entered:

Your Answer
Score Explanation
return count_vowels(hello), count_consonants(bonjour) Incorrect 0.00
Total
0.00 / 1.00
Question ExplanationYou need to write a return statement, and you need to call both count_vowels(...) and count_consonants(...). Remember that there needs to be a space after the word "return".

Question 15

Two function definitions are saved in the same file:

  • A function get_capital has one string parameter that represents a country and returns its capital.
  • A function longer has two string parameters and returns the longer of the two strings.
Variables country1 and country2 refer to str values. Write a one-line expression that produces the longer of the capitals of country1 and country2. Your expression should involve calls on both get_capital and longer.

Note:
  • do not call any functions other than those listed above
  • do not use any unnecessary parentheses

You entered:

Your Answer
Score Explanation
longer (get_capital(country1), get_capital(country2)) Correct 1.00
Total
1.00 / 1.00
Question ExplanationWrite just an expression, not a return statement or an assignment statement or a print statement. Make sure all your opening and closing parentheses match. country1 and country2 are variables, and so should not be quoted; that makes them strings. Do not use more parentheses than necessary.

Question 16

What is the value of average after the following code is executed? 
grade1 = 80
grade2 = 90
average = (grade1 + grade2) / 2
grade1 = 100
Your Answer
Score Explanation
85


85.0 Correct 1.00
95


95.0


Total
1.00 / 1.00
Question ExplanationBe sure to use Python 3, and check your answer by running the code in IDLE. You can then call print(average) to find out it's value.

Question 17



Below is an image of the Python Visualizer in action. The line with the red arrow (line 15) is about to be executed. When we press Forward, function convert_to_minutes will be called, control will move to line 11 of the code (the first line of that function), and a new stack frame will be created containing variable num_hours. What value will num_hours refer to then? (We are looking for a value, not a memory address.)
(If the image is too small, right-click on it and open it in a new browser tab. Then you can zoom in.)

You entered:

Your Answer
Score Explanation
25 Correct 1.00
Total
1.00 / 1.00
Question ExplanationA great way to understand this question is to run it in the Python Visualizer, which is available in the Resources link in the navigation bar.

The line with the red arrow (line 15) is about to be executed. After stepping through to the end of the code below (we can do this by pressing the Last button), how many variables (excluding those that refer to functions) will be on the stack? Recall that the stack is represented by the images on the left-hand side of the model. (If the image is too small, right-click on it and open it in a new browser tab. Then you can zoom in.)

Question 18

Your Answer
Score Explanation
4


5


2 Correct 1.00
3


1


Total
1.00 / 1.00
Question ExplanationA great way to understand this question is to run it in the Python Visualizer, which is available in the Resources link in the navigation bar.

Variable result will not remain on the stack at the end of execution. It is a local variable for function convert_to_minutes, and is no longer accessible when the function has exited.

Remember to exclude variables that refer to functions.