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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _create_file(self, filename):
 """Ensure a new file is created and opened for writing."""

        file_descriptor = os.open(filename, os.O_WRONLY | os.O_CREAT | os.O_EXCL)
        return os.fdopen(file_descriptor, 'w')