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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_value_should_not_be(self, locator, value, strip=False):
 		"""Verifies the element identified by `locator` is not the specified value. 		| *Argument* | *Description* | *Example* | 		| locator | Selenium 2 element locator | id=my_id | 		| value | value it should not be | My Name Is Slim Shady | 		| strip | Boolean, determines whether it should strip the field's value before comparison or not | ${True} / ${False} |"""


		self._info("Verifying element '%s' value is not '%s'" % (locator, value))
		
		element = self._element_find(locator, True, True)
		elem_value = str(element.get_attribute('value'))

		if (strip):
			elem_value = elem_value.strip()
		
		if elem_value == value:
			raise AssertionError("Value was '%s' for element '%s' while it shouldn't have" % (elem_value, locator))