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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 hash(self):
 """Hash the file contents."""

        with open(self.filename, "rb") as fp:
            for content in iter(lambda: fp.read(io.DEFAULT_BUFFER_SIZE), b''):
                self._md5_update(content)
                self._sha2_update(content)
                self._blake_update(content)