Get the output columns for a list of SqlNodes.

    Args:
        nodes: List[SqlNode], the nodes to get output columns from.
        context: CompilationContext, global compilation state and metadata.

    Returns:
        List[Column], list of SqlAlchemy Columns to output for this query.

def _get_output_columns(nodes, context):
    """Get the output columns for a list of SqlNodes.

    Args:
        nodes: List[SqlNode], the nodes to get output columns from.
        context: CompilationContext, global compilation state and metadata.

    Returns:
        List[Column], list of SqlAlchemy Columns to output for this query.
    """
    columns = []
    for node in nodes:
        for sql_output in sql_context_helpers.get_outputs(node, context):
            field_name = sql_output.field_name
            column = sql_context_helpers.get_column(field_name, node, context)
            column = column.label(sql_output.output_name)
            columns.append(column)
    return columns