Helper method to fetch the id or address of a resource by its index

        Args:
            resources (list of objects): The resources to be paginated
            index (integer): The index of the target resource

        Returns:
            str: The address or header_signature of the resource,
                returns an empty string if not found

def id_by_index(index, resources):
        """Helper method to fetch the id or address of a resource by its index

        Args:
            resources (list of objects): The resources to be paginated
            index (integer): The index of the target resource

        Returns:
            str: The address or header_signature of the resource,
                returns an empty string if not found
        """
        if index < 0 or index >= len(resources):
            return ''

        try:
            return resources[index].header_signature
        except AttributeError:
            return resources[index].address