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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_input_by_number(self, number, value):
 """ Set the value of form element by its number in the form :param number: number of element :param value: value which should be set to element """


        sel = XpathSelector(self.form)
        elem = sel.select('.//input[@type="text"]')[number].node()
        return self.set_input(elem.get('name'), value)