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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 calc_sha(self, checksum):
 """ Calculate the checksum of the new exported disk, write it to a file, and update this managers 'exported_metadata'. Args: checksum(str):
 The type of the checksum """

        with LogTask('Calculating {}'.format(checksum)):
            with open(self.dst + '.hash', 'wt') as f:
                sha = utils.get_hash(self.dst, checksum)
                f.write(sha)
            self.exported_metadata[checksum] = sha