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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 areObservableElements(self, elementNames):
 """ Mention if all elements are observable element. :param str ElementName: the element name to evaluate :return: true if is an observable element, otherwise false. :rtype: bool """

        if not(hasattr(elementNames, "__len__")):
            raise TypeError(
                "Element name should be a array of strings." +
                "I receive this {0}"
                .format(elementNames))

        return self._evaluateArray(elementNames)