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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 shift_select(self, first_element, last_element):
 """ Clicks a web element and shift clicks another web element. :param first_element: WebElement instance :param last_element: WebElement instance :return: None """

        self.click(first_element)
        self.shift_click(last_element)