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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 is_opened(components):
 """ Checks if all components are opened. To be checked components must implement [[IOpenable]] interface. If they don't the call to this method returns true. :param components: a list of components that are to be checked. :return: true if all components are opened and false if at least one component is closed. """

        if components == None:
            return True

        result = True
        for component in components:
            result = result and Opener.is_opened_one(component)

        return result