from typing import TextIO
from typing import Dict


def scan_column_names(fp: TextIO, config_dict: Dict, lineno: int) -> int:
    """
    Process columns header, add to config_dict as 'column_names'
    """
    line = fp.readline().strip()
    lineno += 1
    names = line.split(',')
    config_dict['column_names'] = tuple(names)
    return lineno