Reading And Writing Files

Exercise: Reading And Writing Files

How can you read and print the last 3 lines from a file named "data.txt"?

with open("data.txt", "r") as file:
    lines = file.readlines()
    print(lines[-3:])

print_last_lines("data.txt", 3)

with open("data.txt", "r") as file:
    print(file.read(-3))

with open("data.txt", "r") as file:
    for line in file:
        print(line[-3:])

Answer: A

Using lines[-3:] to get the last 3 lines from the list of lines.

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What does the file.writelines() method do?

Writes a single line to the file

Writes multiple lines to the file from a list

Writes the entire content of another file

Writes a specific number of characters to the file

Answer: B

file.writelines() writes multiple lines to the file from a list.

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How can you write a list of strings to a text file named "output.txt" in Python, with each string on a new line?

with open("output.txt", "w") as file:
    strings = ["Hello", "World", "Python"]
    file.write("\n".join(strings))

write_lines("output.txt", ["Hello", "World", "Python"])

text.write("output.txt", ["Hello", "World", "Python"])

with open("output.txt", "w") as file:
    file.writelines(["Hello", "World", "Python"])

Answer: A

Using "\n".join(strings) to join the strings with newline characters.

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What does the os.path.abspath() function do?

Returns the absolute path of the current working directory

Returns the relative path of the specified file

Returns the absolute path of the specified file

Checks if a file exists in the current directory

Answer: A

os.path.abspath() returns the absolute path of the current working directory.

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How can you read and print the first 5 characters from a file named "sample.txt"?

with open("sample.txt", "r") as file:
    print(file.read(5))

print_first_characters("sample.txt", 5)

with open("sample.txt", "r") as file:
    print(file.readline(5))

with open("sample.txt", "r") as file:
    print(file.read(1, 5))

Answer: A

Using file.read(5) to read the first 5 characters.

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