Python File Input and Output 3

Question 1

What does file.seek(0) accomplish?

Accepted Answer

Moves the file pointer to the beginning

Answer

file.seek(0) moves the read/write position back to byte offset 0, which is the start of the file.

Question 2

What is the third argument to file.seek(offset, whence)?

Accepted Answer

The reference position: 0=start, 1=current, 2=end

Answer

The whence argument specifies the reference point: 0 for start of file, 1 for current position, and 2 for end of file.

Question 3

Which module provides the NamedTemporaryFile context manager?

Accepted Answer

tempfile

Answer

The tempfile module provides NamedTemporaryFile, TemporaryFile, and other utilities for creating temporary files.

Question 4

What does file.truncate(n) do?

Accepted Answer

Resizes the file to at most n bytes

Answer

file.truncate(size) resizes the file to at most size bytes; if size is omitted, the current position is used.

Question 5

In Python, which exception is raised when a file is not found?

Accepted Answer

FileNotFoundError

Answer

FileNotFoundError is raised when a file or directory is requested but cannot be found; it is a subclass of OSError.

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