98-381 Exam - Question 27

Question

DRAG DROP -You are writing a function that works with files. You need to ensure that the function returns None if the file does not exist. If the file does exist, the function must return the first line. You write the following code:In which order should you arrange the code segments to complete the function? To answer, move all code segments from the list of code segments to the answer area and arrange them in the correct order. Select and Place:.

Examice · Accepted Answer

References: http://effbot. org/zone/python-with-statement. htm.

JeffJupiter · Answer

I would think the with and if statement should be swapped. If statement should come first and with statement nested in the if block

mallecespedes · Answer

import os
filename = "ExampleFile.csv"

def get_first_line(filename):
    if os.path.isfile(filename):
        with open(filename, 'r') as file:
            return file.readline()
    else:
        return None
        
print(get_first_line(filename))

Daan_peacock · Answer

I got a text file named 'test_file.txt' ready to be read. Checking the two options:

# Option 1: Results in error
import os
def get_first_line(filename, mode):
    with open(filename, 'r') as file:
        if os.path.isfile(filename):
            return file.readline()
        else:
            return

print(get_first_line("test.txt", 'r'))

# Option 2: Reads first line
import os
def get_first_line(filename, mode):
    if os.path.isfile(filename):
        with open(filename, 'r') as file:
            return file.readline()
    else:
        pass

print(get_first_line("test_file.txt", 'r'))

Viki2405 · Answer

import os
def get_data(filename,mode):
	if os.path.isfile(filename):
		with open(filename,'r') as file:
			return file.readline()
	else:
		return None

hedi12 · Answer

i think it's correct too, when we put "with" befor the "if"

Satbabu · Answer

The "if" statement should come before "with" statement, otherwise the code will throw runtime error "FileNotFoundError" if it couldn't find the specified file in "with" statement.

98-381 Exam - Question 27

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