I need to create files of arbitrary size that contain no data. The are potentially quite large. While I could just loop through and write a single null character until I've reached the file size, that seems ugly.

with open(filename,'wb') as f:# what goes here?

What is the efficient, pythonic way to do this?

You can seek to a specific position and write a byte, and the OS will magically make the rest of the file appear.

with open(filename, "wb") as f:f.seek(999999)f.write("\0")

You need to write at least one byte for this to work.