from typing import List


def get_header_row(board: List[List[str]]) -> List[str]:
    """
        Get the row header.
        (Note: this list should only contain numbers, but in str type.)

        Parameters
        ----------
        board: List[List[str]]
            2D array containing all the game detail, including column header, row header and placed buildings.

        Returns
        -------
        row_heder_list: List[str]
            A list containing all the row header.
    """

    return [row[0] for row in board]