OAU CSC 201 Practice Quiz

The code shown above shows a general decorator which can work with any number of arguments.

Objects of type int have no attribute upper().

Tuples are represented with round brackets.

The order of precedence is: %, +. Hence the expression above, on simplification results in 4 + 3 = 7. Hence the result is 7.

+ will append the element to the list.

All the statements will execute successfully but at the cost of reduced readability.

Python has a nifty feature called documentation strings, usually referred to by its shorter name docstrings. DocStrings are an important tool that you should make use of since it helps to document the program better and makes it easier to understand.

The code ‘There are %d %s birds.’ %(4, blue) results in the output: There are 4 blue birds. When we insert more than one value, we should group the values on the right in a tuple.

[::-1] reverses the list.

The code shown above prints the values substituted for a, b, a, in the same order. This operation is performed using the format function. Hence the output of the code is: ‘helloworldhello’.

The @ symbol along with the name of the decorator function can be placed above the definition of the function to be decorated works as an alternate way for decorating a function.

SyntaxError, there shouldn’t be a space between + and = in +=.

Control exits the loop when i becomes 7.

The code shown above prints the appropriate option depending on the conditions given. The condition which matches is (9>0), and hence the output is: good.

~x is equivalent to -(x+1).

math.pow() returns a floating point number.

We use the function append to add an element to the list.

The symbol ‘&’ represents bitwise AND. This gives 1 if both the bits are equal to 1, else it gives 0. The binary form of 15 is 1111 and that of 12 is 1100. Hence on performing the bitwise AND operation, we get 1100, which is equal to 12.

The expression not(10<20) returns false. The expression not(10>30) returns true. The and operation between false and true returns false. Hence the output is false.

True, False and None are capitalized while the others are in lower case.

The code shown above converts the value 255 into hexadecimal, that is, 0xff. The value ‘FF’ into integer. Hence the output of the code shown is: (‘0xff’, 255, 255).

The @ symbol can be used as an alternate way to specify a function that needs to be decorated. The output of the codes shown above is the same. Hence they are equivalent. Therefore this statement is true.

All of the above examples show explicit conversion. However the expression int(’10.8’) results in an error.

In python, power operator is x**y i.e. 2**3=8.

The code shown above shows a general decorator which can work with any number of arguments.

[::-1] reverses the list.

The code shown above demonstrates rebinding using a static method. This can be done with or without a decorator. The output of this code will be 100.

Suppose we have an expression ~A. This is evaluated as: -A – 1. Therefore, the expression ~100 is evaluated as -100 – 1, which is equal to -101.

The order of precedence is: %, +.

Hence the expression above, on simplification results in 4 + 3 = 7.

Hence the result is 7.

SyntaxError, there shouldn’t be a space between + and = in +=.SyntaxError, there shouldn’t be a space between + and = in +=.

The string x is being shortened by one character in each iteration.

Here i i i i i … printed continuously because as the value of i or x isn’t changing, the condition will always evaluate to True. But also here we use a citation marks on “i”, so, here i treated as a string, not like a variable.

NameError, i is not defined.

OverflowError, cannot convert float infinity to integer.

Explanation: { } creates a dictionary not a set. Only set() creates an empty set.

The code shown above returns the number of times a given function has been called. Hence the output of this code is: 3

Let us consider an example wherein a=2. The binary form of 2 is 0010. When we left shift this value by 2, we get 1000, the value of which is 8. Hence if we want to multiply a given number ‘a’ by 4, we can use the expression: a<<2.

The expression int(‘1111’,2) gives the result 15. The expression int(‘1111’, 10) will give the result 1111.

Addition and Subtraction” are at the same precedence level. Similarly, “Multiplication and Division” are at the same precedence level. However, Multiplication and Division operators are at a higher precedence level than Addition and Subtraction operators.

The code shown above returns the address on the function ordi first, after which the word “Ordinary” is printed. Hence the output of this code is:
Address
Ordinary.

eval can be used as a variable.

To write single-line comments in Python use the Hash character (#) at the beginning of the line. It is also called number sign or pound sign. To write multi-line comments, close the text between triple quotes.
Example: “”” comment
text “””

The code shown first adds the element ‘san’ to the set z. The set z is then updated and two more elements, namely, ‘p’ and ‘q’ are added to it. Hence the output is: {‘a’, ‘b’, ‘c’, ‘p’, ‘q’, ‘san’}

Let’s break it down step by step:

Code:

z = set(‘abc’)                        # Create a set with elements from the string ‘abc’

z.add(‘san’)                          # Add the string ‘san’ to the set

z.update(set([‘p’, ‘q’]))             # Add elements ‘p’ and ‘q’ from another set to `z`

z                                     # Display the final set

Step-by-Step Explanation:

Step 1: Create a set

z = set(‘abc’)

• The string ‘abc’ is turned into a set of individual characters:

z = {‘a’, ‘b’, ‘c’}

• Note: Sets do not allow duplicate elements, so each character in ‘abc’ is added only once.

Step 2: Add the string ‘san’

z.add(‘san’)

• The .add() method adds a single element to the set.

• ‘san’ is treated as a single item, not split into characters.

• The set now looks like this:

z = {‘a’, ‘b’, ‘c’, ‘san’}

Step 3: Update the set with set([‘p’, ‘q’])

z.update(set([‘p’, ‘q’]))

• The .update() method adds multiple elements from another set or iterable to the set.

• The elements ‘p’ and ‘q’ are added individually to z.

• The set now looks like this:

z = {‘a’, ‘b’, ‘c’, ‘san’, ‘p’, ‘q’}

Step 4: Display the set

z

• The set contains all unique elements added in previous steps:

{‘a’, ‘b’, ‘c’, ‘san’, ‘p’, ‘q’}

Important Notes:

1. Sets do not allow duplicate values: If an element already exists, adding it again has no effect.

2. Order of elements in a set is unpredictable: Sets are unordered collections, so the display order might differ.

Correct Answer:

c) {‘a’, ‘b’, ‘c’, ‘p’, ‘q’, ‘san’}

The Boolean function returns true if the argument passed to the bool function does not amount to zero. In the first example, the string ‘False’ is passed to the function bool. This does not amount to zero and hence the output is true. In the second function, an empty list is passed to the function bool. Hence the output is false.

Control does not enter the loop because of False.

Loops over the elements of the set and prints them.

If the truth method is not defined, the object is considered true. Hence the output of the code shown above is true.

The code shown above prints the values substituted for p and q in the same order. Note that there is no blank space between p and q. Hence the output is: sanfoundry.

The expression shown above results in the output 456.