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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 append_if_provenance_step( self, title, description, timestamp=None, data=None):
 """Add a if provenance step to the provenance of the metadata :param title: The title of the step. :type title: str :param description: The content of the step :type description: str :param timestamp: the time of the step :type timestamp: datetime, str :param data: The data of the step. :type data: dict """

        step_time = self._provenance.append_if_provenance_step(
            title, description, timestamp, data)
        if step_time > self.last_update:
            self.last_update = step_time