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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 element_should_be_disabled(self, locator, loglevel='INFO'):

 """Verifies that element identified with locator is disabled.
 
 Key attributes for arbitrary elements are `id` and `name`. See
 `introduction` for details about locating elements.
 """

        if self._element_find(locator, True, True).is_enabled():
            self.log_source(loglevel)
            raise AssertionError("Element '%s' should be disabled "
                                 "but did not" % locator)
        self._info("Element '%s' is disabled ." % locator)