def METHOD_NAME(stmt):
    # reset the globals for each run
    global col_list, check_first_select, check_break
    check_first_select=False
    check_break=False
    # populates col_list
    get_column_recurse(stmt.tokens)
    # Fill the array with name cleaned column names
    arr=[]
    for column_identifier in col_list:
        c = pre_process_names(str(column_identifier))
        if c is None:
            try:
                if isinstance(column_identifier, Function):
                    continue
                arr.append(column_identifier.get_name().lower())
            except:
                continue
        else:
            arr.append(c.lower())
    col_list=[]
    return arr