code: def element_value_should_contain(self, locator, expected):
  		
  
  		self._info("Verifying element '%s' value contains '%s'" % (locator, expected))
  		
  		element = self._element_find(locator, True, True)
  		value = str(element.get_attribute('value'))
  		
  		if expected in value:
  			return
  		
  		else:
  			raise AssertionError("Value '%s' did not appear in element '%s'. It's value was '%s'" % (expected, locator, value))
docs: Verifies the element identified by `locator` contains the expected value.
  
  		| *Argument* | *Description* | *Example* |
  		| locator | Selenium 2 element locator | id=my_id |
  		| expected | expected value | Slim Shady |