Returns given Node attribute index at given column.

        :param node: Node.
        :type node: AbstractCompositeNode or GraphModelNode
        :param column: Attribute column.
        :type column: int
        :return: Index.
        :rtype: QModelIndex

def get_attribute_index(self, node, column):
        """
        Returns given Node attribute index at given column.

        :param node: Node.
        :type node: AbstractCompositeNode or GraphModelNode
        :param column: Attribute column.
        :type column: int
        :return: Index.
        :rtype: QModelIndex
        """

        if column > 0 and column < len(self.__horizontal_headers):
            row = node.row()
            return self.createIndex(row, column, node) if row is not None else QModelIndex()