Mastering File I/O in Python 2

Which of the following is the correct way to open a file named `data.txt` for reading in Python?

• `open('data.txt', 'w')`

• `open('data.txt', 'r')`

• `open('data.txt', 'a')`

• `open('data.txt', 'x')`

What is the purpose of using a context manager when working with files in Python?

• To automatically close the file after the block of code is executed

• To read the file line by line

• To write data to the file

• To append data to the file

Which of the following code snippets correctly writes the string "Hello, World!" to a file named `output.txt`?

• `with open('output.txt', 'r') as file: file.write("Hello, World!")`

• `with open('output.txt', 'w') as file: file.write("Hello, World!")`

• `with open('output.txt', 'a') as file: file.write("Hello, World!")`

• `with open('output.txt', 'x') as file: file.write("Hello, World!")`

How can you read all lines of a file into a list in Python?

• `file.readlines()`

• `file.read()`

• `file.readline()`

• `file.readall()`

What does the `with` statement ensure when used with file operations?

• The file is opened in binary mode

• The file is always closed properly

• The file is read-only

• The file is writable

Which method is used to write a list of strings to a file in Python?

• `file.write()`

• `file.writelines()`

• `file.append()`

• `file.insert()`

What is the default mode when opening a file using `open()` in Python?

• Write mode

• Read mode

• Append mode

• Exclusive creation mode

Which of the following is a correct way to read a file line by line using a context manager?

• `with open('file.txt', 'r') as file: for line in file: print(line)`

• `with open('file.txt', 'r') as file: print(file.read())`

• `with open('file.txt', 'r') as file: file.readlines()`

• `with open('file.txt', 'r') as file: file.readline()`

What will happen if you try to open a file that does not exist using `open('file.txt', 'r')`?

• A new file will be created

• An error will be raised

• The file will be opened in write mode

• The file will be opened in append mode

Which of the following modes will allow you to read and write to a file without truncating it?

• `'r'`

• `'w'`

• `'a'`

• `'r+'`