PCEP Practice Exam 5

Which of the following statements is incorrect:

• An indentation in Python language is mandatory

• The '#' is used as single line comments and the """ """ (triple quote) is used as multi-line comments

• We don't need to declare the type of a variable in Python program

• All of these are correct.

Answer explanation

Python is indentation-strict language. We can use # for single line comments or triple quotes for multiple-line comments (usually called DocStrings). Python is a dynamically typed language so we don't need to declare the variable data type.

What will the output be when the following code is executed?

• "Robert, 123455667, Dar es salaam "

• Robert 123455667 Dar es salaam

• SyntaxError

• Robert' 123455667 'Dar es salaam '

Answer explanation

Multiple variables can be assigned values as shown in the example above. Keep in mind that we must have the same number of variables and values, otherwise we will get one of the following errors depending on the situation: TypeError: cannot unpack non-iterable int object if the number of values on the right side is less than the number of variables on the left side. ValueError: too many values to unpack if the number of values on the right side is larger than the number of variables on the left side.

What will be the output when the following code is executed?

• \n:\n:\n

• :

  :

  :

• Three blank lines

• error

Answer explanation

The end = "\n\n\n" will append three newline characters (\n) after printing out the text. Since there are no objects provided to the print() function to be printed, only the three empty lines will be printed. The sep is redundant in this code as there is no text to be printed.

What will be the output when the following code is executed?

• 25

• 256

• error

• 25.6

Answer explanation

The int function will round down to the previous whole number, in this case 25.

Which of the following statements is incorrect (select all that apply):

• The bool("123") will return True

• The bool("") will return True

• The bool({}) will return False

• The bool(-1) will return False

Answer explanation

The bool function when provided an empty string, empty object, or zero, will return False. In any other case, it will return True. bool("") evaluates to False as it is an empty string and the bool(-1) evaluates True as -1 is a non-zero value.

What would be the output of the following code:

• 1

• 2

• 4

• 25

Answer explanation

The exponentiation will take precedence over modulo, hence the above expression can be simplified to 2 % 25 . The remainder of the division of 25 by 2 is 2.

What will be the output when the following code is executed?

• False

• True

• SyntaxError

• error

Answer explanation

The if condition will evaluate to False as since p is not less than 10, q is not greater than 20 and r is not greater than 30. Hence the else block will get executed. Note: In this example, all of the conditions in the if statement evaluate to False. However in another scenario, even if only one of them is False, the if block would not get executed.

What will be the output when the follownig code is executed?

• 0b00111

• 0b11111

• 0b11110

• 0b11100

Answer explanation

The left shift operator shifts the bits to the left by the given number. The current 111 will be moved by 2 bits with 0's filled in, hence 11100

What will be the output of the following print statements?

• False

  True

• True

  True

• False

  False

• True

  False

Answer explanation

The is operator is an identity operator, it checks whether both the operands refer to the same object or not. lst1 and lst2 are two different objects (despite their content being the same). The == operator checks if the values stored in the variables are equal to each other, which is True in this case.

What will be the output when the follownig code is executed?

• error

• Type Error: object of type 'int' has no len()

• 4

• 0

Answer explanation

The len() function cannot be used on integers. It can only be used on sequences such as strings, lists, tuples.