import csv


def read_csv_header(src_file, return_second_row=False):
    """Returns a list containing the values from the first row (or second row) of the given CSV
    file or None if the file is empty.

    :param src_file: The CSV file to read.
    :param return_second_row: boolean to return 2nd row instead
    :return: The first row or None if empty.
    """
    with open(src_file) as csv_file:
        for row in csv.reader(csv_file):
            if return_second_row:
                return_second_row = False
                continue
            return list(row)