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Python Programming - Generators

Exercise : Generators - General Questions
  • Generators - General Questions
66.
What is the purpose of the itertools.accumulate() function when used with generators?
It generates the cumulative sum of elements in the generator
It filters elements based on a specified condition
It stops the generator after one iteration
It interleaves values from different generators
Answer: Option
Explanation:
itertools.accumulate() generates the cumulative sum of elements in the generator, creating an iterator that yields the accumulated results.
67.
How does the itertools.islice() function differ from itertools.takewhile() when used with generators?
They are equivalent in functionality
itertools.islice() allows for arbitrary slicing, while itertools.takewhile() stops based on a condition
itertools.takewhile() allows for arbitrary slicing, while itertools.islice() stops based on a condition
itertools.islice() modifies the original generator, while itertools.takewhile() creates a new generator
Answer: Option
Explanation:
itertools.islice() allows for arbitrary slicing by specifying start, stop, and step parameters, while itertools.takewhile() stops yielding elements when a specified condition becomes false. 
import itertools

def my_generator():
    for i in range(10):
        yield i

sliced_iterable = itertools.islice(my_generator(), 2, 7)
takewhile_iterable = itertools.takewhile(lambda x: x < 5, my_generator())

print(list(sliced_iterable))      # Output: [2, 3, 4, 5, 6]
print(list(takewhile_iterable))   # Output: [0, 1, 2, 3, 4]
68.
How does the generator.throw(StopIteration) method differ from raise StopIteration when used with a generator?
They have the same effect on the generator
generator.throw(StopIteration) stops the generator and raises a StopIteration exception, while raise StopIteration is used outside the generator
raise StopIteration stops the generator and raises a StopIteration exception, while generator.throw(StopIteration) is used outside the generator
generator.throw(StopIteration) raises a ValueError
Answer: Option
Explanation:
generator.throw(StopIteration) is used to stop the generator and raise a StopIteration exception inside the generator. raise StopIteration is used outside the generator to signal the end of the iteration.
69.
What happens if a generator function contains a return value statement followed by a yield statement?
It raises a GeneratorExit exception
It raises a StopIteration exception
It returns the specified value and stops the generator
It is a syntax error; return and yield cannot be used together
Answer: Option
Explanation:
If a generator function contains both return value and yield statements, it returns the specified value and stops the generator. 
def my_generator():
    return 42
    yield  # This statement is never reached

# Example usage
gen = my_generator()
result = next(gen, None)
print(result)  # Output: 42
70.
What is the purpose of the itertools.starmap() function when used with generators?
It applies a function to pairs of elements from multiple generators
It filters elements based on a specified condition
It stops the generator after one iteration
It applies a function to elements from a single generator
Answer: Option
Explanation:
itertools.starmap() applies a function to elements from a single generator, using argument unpacking to provide the function with multiple arguments.
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