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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 delete(self, index=None):
 """ Removes either the specified Instance or all Instance objects. :param index: the 0-based index of the instance to remove :type index: int """

        if index is None:
            javabridge.call(self.jobject, "delete", "()V")
        else:
            javabridge.call(self.jobject, "delete", "(I)V", index)