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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 touch(self, mode=0o666, exist_ok=True):
 """ Create a file if it doesn't exist. Mode is ignored by Artifactory. """

        if self.exists() and not exist_ok:
            raise OSError(17, "File exists", str(self))

        self._accessor.touch(self)