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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 set_params(self, subs=None, numticks=None):
 """ Set parameters within this locator. Parameters subs : array, optional Subtick values, as multiples of the main ticks. numticks : array, optional Number of ticks. """

        if numticks is not None:
            self.numticks = numticks
        if subs is not None:
            self._subs = subs