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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 active_element(self):
 """ Returns the element with focus, or BODY if nothing has focus. :Usage: :: element = driver.switch_to.active_element """

        if self._driver.w3c:
            return self._driver.execute(Command.W3C_GET_ACTIVE_ELEMENT)['value']
        else:
            return self._driver.execute(Command.GET_ACTIVE_ELEMENT)['value']