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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 get_checksum_metadata_tag(self):
 """ Returns a map of checksum values by the name of the hashing function that produced it."""

        if not self._checksums:
            print("Warning: No checksums have been computed for this file.")
        return {str(_hash_name): str(_hash_value) for _hash_name, _hash_value in self._checksums.items()}