ExamAdept

What is the purpose of the __str__() method in Python classes?

A:

To define class attributes

B:

To customize the behavior when an instance is subtracted from another instance

C:

To represent the object as a string for display purposes

D:

To create a new instance of the class

Answer: C

The __str__() method is used to provide a human-readable string representation of an object for display purposes.

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What is the output of the following Python code?

class Shape:
    def draw(self):
        return "Drawing a shape"

class Circle(Shape):
    def draw(self):
        return "Drawing a circle"

class Square(Shape):
    def draw(self):
        return "Drawing a square"

def display_shape_info(shape):
    return shape.draw()

circle = Circle()
square = Square()

print(display_shape_info(circle))
print(display_shape_info(square))

A:

Drawing a shape

B:

Drawing a circle\nDrawing a square

C:

Drawing a square\nDrawing a circle

D:

Drawing a circle\nDrawing a circle

Answer: B

The display_shape_info() function calls the draw() method of the given shape, resulting in the specific drawing for each shape.

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What is the purpose of the __eq__() method in Python classes in the context of polymorphism?

A:

To customize the behavior when an instance is checked for equality using the == operator

B:

To create a new instance of the class

C:

To define class attributes

D:

To customize the behavior when an item is accessed using square brackets on an instance

Answer: A

The __eq__() method is used to customize the behavior when an instance is checked for equality using the == operator, allowing for polymorphic behavior.

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Which of the following is an example of polymorphism through "operator overloading"?

A:

Using the + operator to concatenate strings

B:

Using the + operator to add two numbers

C:

Using the + operator to access a list element

D:

Using the + operator to define a custom behavior in a class

Answer: D

Polymorphism through operator overloading in Python involves defining custom behavior for operators in a class, such as using __add__() for the + operator.

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How does Python achieve polymorphism through "method overloading"?

A:

By allowing a function to take different types of arguments

B:

By automatically resolving conflicts using the first defined method

C:

By using the C3 linearization algorithm to determine method resolution order

D:

By allowing a function to be defined with the same name but different parameters

Answer: D

Polymorphism through method overloading in Python involves allowing a function to be defined with the same name but different parameters.

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Questions for: Polymorphism