You are running a Python script that is supposed to write data to an open file, but discover that the file contents are not updating even after the script finishes. What is most likely the issue?

The file was not closed using the close $0$ method.

The file is not being written to using the dumpO method.

The file is not being updated because it doesn't exist.

The file was opened using $\text{'}w\text{'}$ instead of $\text{'}b\text{'}$ as the mode string.