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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 update(self, sequence=None, **mapping):
 """Add multiple elements to the fact."""

        if sequence is not None:
            if isinstance(sequence, dict):
                for slot in sequence:
                    self[slot] = sequence[slot]
            else:
                for slot, value in sequence:
                    self[slot] = value
        if mapping:
            for slot in sequence:
                self[slot] = sequence[slot]