Reading And Writing Files

Exercise: Reading And Writing Files

What is the purpose of the os.path.isdir() function?

Checks if a file exists

Checks if a path is a regular file

Checks if a path points to a directory

Checks if a file is empty

Answer: C

os.path.isdir() checks if a path points to a directory.

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How can you determine the number of lines in a file named "data.txt"?

lines = count_lines("data.txt")
print(lines)

with open("data.txt", "r") as file:
    lines = len(file.readlines())
    print(lines)

with open("data.txt", "r") as file:
    lines = file.linecount()
    print(lines)

if lines_exist("data.txt"):
    print(line_count("data.txt"))

Answer: B

Using readlines() and len() to count the number of lines in the file.

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What is the purpose of the shutil.move() function?

To move a file or directory to a different location

To copy the contents of a file

To remove a file

To check if a file is empty

Answer: A

shutil.move() is used to move a file or directory to a different location.

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How can you read and print only the lines that start with "Error:" from a log file named "logfile.txt"?

lines = open("logfile.txt").readlines()
for line in lines:
    if line.startswith("Error:"):
        print(line)

print_error_lines("logfile.txt")

with open("logfile.txt", "r") as file:
    print(file.read("Error:"))

with open("logfile.txt", "r") as file:
    for line in file:
        if "Error:" in line:
            print(line)

Answer: A

Using startswith() to filter and print lines starting with "Error:".

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What is the purpose of the os.rename() function?

To remove a file

To rename a file or directory

To copy a file

To check if a file exists

Answer: B

os.rename() is used to rename a file or directory in Python.

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