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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 startswith(self, prefix):
 """ Construct a Filter matching values starting with ``prefix``. Parameters prefix : str String prefix against which to compare values produced by ``self``. Returns ------- matches : Filter Filter returning True for all sid/date pairs for which ``self`` produces a string starting with ``prefix``. """

        return ArrayPredicate(
            term=self,
            op=LabelArray.startswith,
            opargs=(prefix,),
        )