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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_corner(self, time):
 """ Gets the corner array indices of the STObject at a given time that corresponds to the upper left corner of the bounding box for the STObject. Args: time: time at which the corner is being extracted. Returns: corner index. """

        if self.start_time <= time <= self.end_time:
            diff = time - self.start_time
            return self.i[diff][0, 0], self.j[diff][0, 0]
        else:
            return -1, -1