file - Python, open for writing if exists, otherwise raise error -

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is there option can pass open() cause ioerror when trying write nonexistent file? using python read , write block devices via symlinks, , if link missing want raise error rather create regular file. know add check see if file exists , manually raise error, prefer use built-in if exists.

current code looks this:

device = open(device_path, 'wb', 0) device.write(data) device.close()

yes. 

open(path, 'r+b')

specifying "r" option means file must exist , can read. specifying "+" means can write , positioned @ end. https://docs.python.org/3/library/functions.html?#open


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